diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/README.md b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/README.md
new file mode 100644
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--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/README.md
@@ -0,0 +1,279 @@
+<!--
+
+@license Apache-2.0
+
+Copyright (c) 2026 The Stdlib Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+-->
+
+# Logarithm of Probability Density Function
+
+> [Wald][wald-distribution] distribution logarithm of [probability density function][pdf].
+
+<section class="intro">
+
+The [probability density function][pdf] for a [Wald][wald-distribution] random variable is
+
+<!-- <equation class="equation" label="eq:wald_pdf" align="center" raw="f(x;\mu,\lambda)=\sqrt{\frac{\lambda}{2\pi x^3}}\exp\left(-\frac{\lambda(x-\mu)^2}{2\mu^2 x}\right)" alt="Probability density function (PDF) for a Wald distribution."> -->
+
+```math
+f(x;\mu,\lambda) = \sqrt{\frac{\lambda}{2\pi x^3}}\,\exp\!\left(-\frac{\lambda(x-\mu)^2}{2\mu^2 x}\right)
+```
+
+<!-- </equation> -->
+
+where `μ > 0` is the mean and `λ > 0` is the shape parameter.
+
+</section>
+
+<!-- /.intro -->
+
+<section class="usage">
+
+## Usage
+
+```javascript
+var logpdf = require( '@stdlib/stats/base/dists/wald/logpdf' );
+```
+
+#### logpdf( x, mu, lambda )
+
+Evaluates the natural logarithm of the [probability density function][pdf] (PDF) for a [Wald][wald-distribution] distribution with parameters `mu` (mean) and `lambda` (shape parameter).
+
+```javascript
+var y = logpdf( 2.0, 2.0, 1.0 );
+// returns ~-1.959
+
+y = logpdf( 1.0, 2.0, 1.0 );
+// returns ~-1.044
+
+y = logpdf( 4.0, 2.0, 1.0 );
+// returns ~-3.123
+```
+
+If provided `NaN` as any argument, the function returns `NaN`.
+
+```javascript
+var y = logpdf( NaN, 2.0, 1.0 );
+// returns NaN
+
+y = logpdf( 2.0, NaN, 1.0 );
+// returns NaN
+
+y = logpdf( 2.0, 2.0, NaN );
+// returns NaN
+```
+
+If provided `mu <= 0` or `lambda < 0`, the function returns `NaN`.
+
+```javascript
+var y = logpdf( 2.0, 0.0, -3.0 );
+// returns NaN
+
+y = logpdf( 2.0, -1.0, -2.0 );
+// returns NaN
+
+y = logpdf( 2.0, -2.0, -1.0 );
+// returns NaN
+```
+
+If provided `x <= 0`, the function returns `-Infinity`.
+
+```javascript
+var y = logpdf( 0.0, 2.0, 1.0 );
+// returns -Infinity
+
+y = logpdf( -1.0, 2.0, 1.0 );
+// returns -Infinity
+```
+
+If `lambda = 0`, the function evaluates the logarithm of the [PDF][pdf] of a [degenerate distribution][degenerate-distribution] centered at `mu`.
+
+```javascript
+var y = logpdf( 2.0, 8.0, 0.0 );
+// returns -Infinity
+
+y = logpdf( 8.0, 8.0, 0.0 );
+// returns Infinity
+
+y = logpdf( 10.0, 8.0, 0.0 );
+// returns -Infinity
+```
+
+#### logpdf.factory( mu, lambda )
+
+Returns a function for evaluating the natural logarithm of the [probability density function][pdf] of a [Wald][wald-distribution] distribution with parameters `mu` and `lambda`.
+
+```javascript
+var mylogpdf = logpdf.factory( 1.0, 1.0 );
+
+var y = mylogpdf( 2.0 );
+// returns ~-2.209
+
+y = mylogpdf( 8.0 );
+// returns ~-7.101
+```
+
+</section>
+
+<!-- /.usage -->
+
+<section class="examples">
+
+## Examples
+
+<!-- eslint no-undef: "error" -->
+
+```javascript
+var uniform = require( '@stdlib/random/array/uniform' );
+var logEachMap = require( '@stdlib/console/log-each-map' );
+var EPS = require( '@stdlib/constants/float64/eps' );
+var logpdf = require( '@stdlib/stats/base/dists/wald/logpdf' );
+
+var opts = {
+    'dtype': 'float64'
+};
+var x = uniform( 10, EPS, 10.0, opts );
+var mu = uniform( 10, EPS, 10.0, opts );
+var lambda = uniform( 10, EPS, 20.0, opts );
+
+logEachMap( 'x: %0.4f, μ: %0.4f, λ: %0.4f, ln(f(x;μ,λ)): %0.4f', x, mu, lambda, logpdf );
+```
+
+</section>
+
+<!-- /.examples -->
+
+<!-- C interface documentation. -->
+
+* * *
+
+<section class="c">
+
+## C APIs
+
+<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->
+
+<section class="intro">
+
+</section>
+
+<!-- /.intro -->
+
+<!-- C usage documentation. -->
+
+<section class="usage">
+
+### Usage
+
+```c
+#include "stdlib/stats/base/dists/wald/logpdf.h"
+```
+
+#### stdlib_base_dists_wald_logpdf( x, mu, lambda )
+
+Evaluates the natural logarithm of the [probability density function][pdf] (PDF) for a [Wald][wald-distribution] distribution with parameters `mu` (mean) and `lambda` (shape parameter).
+
+```c
+double out = stdlib_base_dists_wald_logpdf( 2.0, 1.0, 1.0 );
+// returns ~-2.209
+```
+
+The function accepts the following arguments:
+
+-   **x**: `[in] double` input value.
+-   **mu**: `[in] double` mean.
+-   **lambda**: `[in] double` shape parameter.
+
+```c
+double stdlib_base_dists_wald_logpdf( const double x, const double mu, const double lambda );
+```
+
+</section>
+
+<!-- /.usage -->
+
+<!-- C API usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
+
+<section class="notes">
+
+</section>
+
+<!-- /.notes -->
+
+<!-- C API usage examples. -->
+
+<section class="examples">
+
+### Examples
+
+```c
+#include "stdlib/stats/base/dists/wald/logpdf.h"
+#include "stdlib/constants/float64/eps.h"
+#include <stdlib.h>
+#include <stdio.h>
+#include <time.h>
+
+static double random_uniform( const double min, const double max ) {
+    double v = (double)rand() / ( (double)RAND_MAX + 1.0 );
+    return min + ( v*(max-min) );
+}
+
+int main( void ) {
+    double lambda;
+    double mu;
+    double x;
+    double y;
+    int i;
+
+    for ( i = 0; i < 10; i++ ) {
+        x = random_uniform( STDLIB_CONSTANT_FLOAT64_EPS, 10.0 );
+        mu = random_uniform( STDLIB_CONSTANT_FLOAT64_EPS, 10.0 );
+        lambda = random_uniform( STDLIB_CONSTANT_FLOAT64_EPS, 10.0 );
+        y = stdlib_base_dists_wald_logpdf( x, mu, lambda );
+        printf( "x: %lf, μ: %lf, λ: %lf, ln(f(x;μ,λ)): %lf\n", x, mu, lambda, y );
+    }
+}
+```
+
+</section>
+
+<!-- /.examples -->
+
+</section>
+
+<!-- /.c -->
+
+<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->
+
+<section class="related">
+
+</section>
+
+<!-- /.related -->
+
+<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
+
+<section class="links">
+
+[pdf]: https://en.wikipedia.org/wiki/Probability_density_function
+
+[wald-distribution]: https://en.wikipedia.org/wiki/Inverse_Gaussian_distribution
+
+[degenerate-distribution]: https://en.wikipedia.org/wiki/Degenerate_distribution
+
+</section>
+
+<!-- /.links -->
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/benchmark/benchmark.js b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/benchmark/benchmark.js
new file mode 100644
index 000000000000..849c238ea6ce
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/benchmark/benchmark.js
@@ -0,0 +1,90 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var bench = require( '@stdlib/bench' );
+var uniform = require( '@stdlib/random/array/uniform' );
+var isnan = require( '@stdlib/math/base/assert/is-nan' );
+var EPS = require( '@stdlib/constants/float64/eps' );
+var format = require( '@stdlib/string/format' );
+var pkg = require( './../package.json' ).name;
+var logpdf = require( './../lib' );
+
+
+// MAIN //
+
+bench( pkg, function benchmark( b ) {
+	var arrayOpts;
+	var lambda;
+	var mu;
+	var x;
+	var y;
+	var i;
+
+	arrayOpts = {
+		'dtype': 'float64'
+	};
+	x = uniform( 100, EPS, 100.0, arrayOpts );
+	mu = uniform( 100, EPS, 50.0, arrayOpts );
+	lambda = uniform( 100, EPS, 20.0, arrayOpts );
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		y = logpdf( x[ i % x.length ], mu[ i % mu.length ], lambda[ i % lambda.length ] );
+		if ( isnan( y ) ) {
+			b.fail( 'should not return NaN' );
+		}
+	}
+	b.toc();
+	if ( isnan( y ) ) {
+		b.fail( 'should not return NaN' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});
+
+bench( format( '%s:factory', pkg ), function benchmark( b ) {
+	var arrayOpts;
+	var mylogpdf;
+	var x;
+	var y;
+	var i;
+
+	arrayOpts = {
+		'dtype': 'float64'
+	};
+	mylogpdf = logpdf.factory( 1.0, 1.5 );
+	x = uniform( 100, EPS, 10.0, arrayOpts );
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		y = mylogpdf( x[ i % x.length ] );
+		if ( isnan( y ) ) {
+			b.fail( 'should not return NaN' );
+		}
+	}
+	b.toc();
+	if ( isnan( y ) ) {
+		b.fail( 'should not return NaN' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/benchmark/benchmark.native.js b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/benchmark/benchmark.native.js
new file mode 100644
index 000000000000..9aecf7d7bc88
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/benchmark/benchmark.native.js
@@ -0,0 +1,71 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var resolve = require( 'path' ).resolve;
+var bench = require( '@stdlib/bench' );
+var uniform = require( '@stdlib/random/array/uniform' );
+var isnan = require( '@stdlib/math/base/assert/is-nan' );
+var tryRequire = require( '@stdlib/utils/try-require' );
+var EPS = require( '@stdlib/constants/float64/eps' );
+var format = require( '@stdlib/string/format' );
+var pkg = require( './../package.json' ).name;
+
+
+// VARIABLES //
+
+var logpdf = tryRequire( resolve( __dirname, './../lib/native.js' ) );
+var opts = {
+	'skip': ( logpdf instanceof Error )
+};
+
+
+// MAIN //
+
+bench( format( '%s::native', pkg ), opts, function benchmark( b ) {
+	var arrayOpts;
+	var lambda;
+	var mu;
+	var x;
+	var y;
+	var i;
+
+	arrayOpts = {
+		'dtype': 'float64'
+	};
+	x = uniform( 100, EPS, 100.0, arrayOpts );
+	mu = uniform( 100, EPS, 50.0, arrayOpts );
+	lambda = uniform( 100, EPS, 20.0, arrayOpts );
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		y = logpdf( x[ i % x.length ], mu[ i % mu.length ], lambda[ i % lambda.length ] );
+		if ( isnan( y ) ) {
+			b.fail( 'should not return NaN' );
+		}
+	}
+	b.toc();
+	if ( isnan( y ) ) {
+		b.fail( 'should not return NaN' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/benchmark/c/Makefile b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/benchmark/c/Makefile
new file mode 100644
index 000000000000..979768abbcec
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/benchmark/c/Makefile
@@ -0,0 +1,146 @@
+#/
+# @license Apache-2.0
+#
+# Copyright (c) 2026 The Stdlib Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#/
+
+# VARIABLES #
+
+ifndef VERBOSE
+	QUIET := @
+else
+	QUIET :=
+endif
+
+# Determine the OS ([1][1], [2][2]).
+#
+# [1]: https://en.wikipedia.org/wiki/Uname#Examples
+# [2]: http://stackoverflow.com/a/27776822/2225624
+OS ?= $(shell uname)
+ifneq (, $(findstring MINGW,$(OS)))
+	OS := WINNT
+else
+ifneq (, $(findstring MSYS,$(OS)))
+	OS := WINNT
+else
+ifneq (, $(findstring CYGWIN,$(OS)))
+	OS := WINNT
+else
+ifneq (, $(findstring Windows_NT,$(OS)))
+	OS := WINNT
+endif
+endif
+endif
+endif
+
+# Define the program used for compiling C source files:
+ifdef C_COMPILER
+	CC := $(C_COMPILER)
+else
+	CC := gcc
+endif
+
+# Define the command-line options when compiling C files:
+CFLAGS ?= \
+	-std=c99 \
+	-O3 \
+	-Wall \
+	-pedantic
+
+# Determine whether to generate position independent code ([1][1], [2][2]).
+#
+# [1]: https://gcc.gnu.org/onlinedocs/gcc/Code-Gen-Options.html#Code-Gen-Options
+# [2]: http://stackoverflow.com/questions/5311515/gcc-fpic-option
+ifeq ($(OS), WINNT)
+	fPIC ?=
+else
+	fPIC ?= -fPIC
+endif
+
+# List of includes (e.g., `-I /foo/bar -I /beep/boop/include`):
+INCLUDE ?=
+
+# List of source files:
+SOURCE_FILES ?=
+
+# List of libraries (e.g., `-lopenblas -lpthread`):
+LIBRARIES ?=
+
+# List of library paths (e.g., `-L /foo/bar -L /beep/boop`):
+LIBPATH ?=
+
+# List of C targets:
+c_targets := benchmark.out
+
+
+# RULES #
+
+#/
+# Compiles source files.
+#
+# @param {string} [C_COMPILER] - C compiler (e.g., `gcc`)
+# @param {string} [CFLAGS] - C compiler options
+# @param {(string|void)} [fPIC] - compiler flag determining whether to generate position independent code (e.g., `-fPIC`)
+# @param {string} [INCLUDE] - list of includes (e.g., `-I /foo/bar -I /beep/boop/include`)
+# @param {string} [SOURCE_FILES] - list of source files
+# @param {string} [LIBPATH] - list of library paths (e.g., `-L /foo/bar -L /beep/boop`)
+# @param {string} [LIBRARIES] - list of libraries (e.g., `-lopenblas -lpthread`)
+#
+# @example
+# make
+#
+# @example
+# make all
+#/
+all: $(c_targets)
+
+.PHONY: all
+
+#/
+# Compiles C source files.
+#
+# @private
+# @param {string} CC - C compiler (e.g., `gcc`)
+# @param {string} CFLAGS - C compiler options
+# @param {(string|void)} fPIC - compiler flag determining whether to generate position independent code (e.g., `-fPIC`)
+# @param {string} INCLUDE - list of includes (e.g., `-I /foo/bar`)
+# @param {string} SOURCE_FILES - list of source files
+# @param {string} LIBPATH - list of library paths (e.g., `-L /foo/bar`)
+# @param {string} LIBRARIES - list of libraries (e.g., `-lopenblas`)
+#/
+$(c_targets): %.out: %.c
+	$(QUIET) $(CC) $(CFLAGS) $(fPIC) $(INCLUDE) -o $@ $(SOURCE_FILES) $< $(LIBPATH) -lm $(LIBRARIES)
+
+#/
+# Runs compiled benchmarks.
+#
+# @example
+# make run
+#/
+run: $(c_targets)
+	$(QUIET) ./$<
+
+.PHONY: run
+
+#/
+# Removes generated files.
+#
+# @example
+# make clean
+#/
+clean:
+	$(QUIET) -rm -f *.o *.out
+
+.PHONY: clean
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/benchmark/c/benchmark.c b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/benchmark/c/benchmark.c
new file mode 100644
index 000000000000..5b62d5022b31
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/benchmark/c/benchmark.c
@@ -0,0 +1,143 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+#include "stdlib/stats/base/dists/wald/logpdf.h"
+#include "stdlib/constants/float64/eps.h"
+#include <stdlib.h>
+#include <stdio.h>
+#include <math.h>
+#include <time.h>
+#include <sys/time.h>
+
+#define NAME "wald-logpdf"
+#define ITERATIONS 1000000
+#define REPEATS 3
+
+/**
+* Prints the TAP version.
+*/
+static void print_version( void ) {
+	printf( "TAP version 13\n" );
+}
+
+/**
+* Prints the TAP summary.
+*
+* @param total     total number of tests
+* @param passing   total number of passing tests
+*/
+static void print_summary( int total, int passing ) {
+	printf( "#\n" );
+	printf( "1..%d\n", total ); // TAP plan
+	printf( "# total %d\n", total );
+	printf( "# pass  %d\n", passing );
+	printf( "#\n" );
+	printf( "# ok\n" );
+}
+
+/**
+* Prints benchmarks results.
+*
+* @param elapsed   elapsed time in seconds
+*/
+static void print_results( double elapsed ) {
+	double rate = (double)ITERATIONS / elapsed;
+	printf( "  ---\n" );
+	printf( "  iterations: %d\n", ITERATIONS );
+	printf( "  elapsed: %0.9f\n", elapsed );
+	printf( "  rate: %0.9f\n", rate );
+	printf( "  ...\n" );
+}
+
+/**
+* Returns a clock time.
+*
+* @return clock time
+*/
+static double tic( void ) {
+	struct timeval now;
+	gettimeofday( &now, NULL );
+	return (double)now.tv_sec + (double)now.tv_usec/1.0e6;
+}
+
+/**
+* Generates a random number on the interval [min,max).
+*
+* @param min    minimum value (inclusive)
+* @param max    maximum value (exclusive)
+* @return       random number
+*/
+static double random_uniform( const double min, const double max ) {
+	double v = (double)rand() / ( (double)RAND_MAX + 1.0 );
+	return min + ( v*(max-min) );
+}
+
+/**
+* Runs a benchmark.
+*
+* @return elapsed time in seconds
+*/
+static double benchmark( void ) {
+	double lambda[ 100 ];
+	double mu[ 100 ];
+	double x[ 100 ];
+	double elapsed;
+	double y;
+	double t;
+	int i;
+
+	for ( i = 0; i < 100; i++ ) {
+		x[ i ] = random_uniform( STDLIB_CONSTANT_FLOAT64_EPS, 100.0 );
+		mu[ i ] = random_uniform( STDLIB_CONSTANT_FLOAT64_EPS, 50.0 );
+		lambda[ i ] = random_uniform( STDLIB_CONSTANT_FLOAT64_EPS, 20.0 );
+	}
+
+	t = tic();
+	for ( i = 0; i < ITERATIONS; i++ ) {
+		y = stdlib_base_dists_wald_logpdf( x[ i%100 ], mu[ i%100 ], lambda[ i%100 ] );
+		if ( y != y ) {
+			printf( "should not return NaN\n" );
+			break;
+		}
+	}
+	elapsed = tic() - t;
+	if ( y != y ) {
+		printf( "should not return NaN\n" );
+	}
+	return elapsed;
+}
+
+/**
+* Main execution sequence.
+*/
+int main( void ) {
+	double elapsed;
+	int i;
+
+	// Use the current time to seed the random number generator:
+	srand( time( NULL ) );
+
+	print_version();
+	for ( i = 0; i < REPEATS; i++ ) {
+		printf( "# c::%s\n", NAME );
+		elapsed = benchmark();
+		print_results( elapsed );
+		printf( "ok %d benchmark finished\n", i+1 );
+	}
+	print_summary( REPEATS, REPEATS );
+}
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/binding.gyp b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/binding.gyp
new file mode 100644
index 000000000000..0d6508a12e99
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/binding.gyp
@@ -0,0 +1,170 @@
+# @license Apache-2.0
+#
+# Copyright (c) 2026 The Stdlib Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# A `.gyp` file for building a Node.js native add-on.
+#
+# [1]: https://gyp.gsrc.io/docs/InputFormatReference.md
+# [2]: https://gyp.gsrc.io/docs/UserDocumentation.md
+{
+  # List of files to include in this file:
+  'includes': [
+    './include.gypi',
+  ],
+
+  # Define variables to be used throughout the configuration for all targets:
+  'variables': {
+    # Target name should match the add-on export name:
+    'addon_target_name%': 'addon',
+
+    # Set variables based on the host OS:
+    'conditions': [
+      [
+        'OS=="win"',
+        {
+          # Define the object file suffix:
+          'obj': 'obj',
+        },
+        {
+          # Define the object file suffix:
+          'obj': 'o',
+        }
+      ], # end condition (OS=="win")
+    ], # end conditions
+  }, # end variables
+
+  # Define compile targets:
+  'targets': [
+
+    # Target to generate an add-on:
+    {
+      # The target name should match the add-on export name:
+      'target_name': '<(addon_target_name)',
+
+      # Define dependencies:
+      'dependencies': [],
+
+      # Define directories which contain relevant include headers:
+      'include_dirs': [
+        # Local include directory:
+        '<@(include_dirs)',
+      ],
+
+      # List of source files:
+      'sources': [
+        '<@(src_files)',
+      ],
+
+      # Settings which should be applied when a target's object files are used as linker input:
+      'link_settings': {
+        # Define libraries:
+        'libraries': [
+          '<@(libraries)',
+        ],
+
+        # Define library directories:
+        'library_dirs': [
+          '<@(library_dirs)',
+        ],
+      },
+
+      # C/C++ compiler flags:
+      'cflags': [
+        # Enable commonly used warning options:
+        '-Wall',
+
+        # Aggressive optimization:
+        '-O3',
+      ],
+
+      # C specific compiler flags:
+      'cflags_c': [
+        # Specify the C standard to which a program is expected to conform:
+        '-std=c99',
+      ],
+
+      # C++ specific compiler flags:
+      'cflags_cpp': [
+        # Specify the C++ standard to which a program is expected to conform:
+        '-std=c++11',
+      ],
+
+      # Linker flags:
+      'ldflags': [],
+
+      # Apply conditions based on the host OS:
+      'conditions': [
+        [
+          'OS=="mac"',
+          {
+            # Linker flags:
+            'ldflags': [
+              '-undefined dynamic_lookup',
+              '-Wl,-no-pie',
+              '-Wl,-search_paths_first',
+            ],
+          },
+        ], # end condition (OS=="mac")
+        [
+          'OS!="win"',
+          {
+            # C/C++ flags:
+            'cflags': [
+              # Generate platform-independent code:
+              '-fPIC',
+            ],
+          },
+        ], # end condition (OS!="win")
+      ], # end conditions
+    }, # end target <(addon_target_name)
+
+    # Target to copy a generated add-on to a standard location:
+    {
+      'target_name': 'copy_addon',
+
+      # Declare that the output of this target is not linked:
+      'type': 'none',
+
+      # Define dependencies:
+      'dependencies': [
+        # Require that the add-on be generated before building this target:
+        '<(addon_target_name)',
+      ],
+
+      # Define a list of actions:
+      'actions': [
+        {
+          'action_name': 'copy_addon',
+          'message': 'Copying addon...',
+
+          # Explicitly list the inputs in the command-line invocation below:
+          'inputs': [],
+
+          # Declare the expected outputs:
+          'outputs': [
+            '<(addon_output_dir)/<(addon_target_name).node',
+          ],
+
+          # Define the command-line invocation:
+          'action': [
+            'cp',
+            '<(PRODUCT_DIR)/<(addon_target_name).node',
+            '<(addon_output_dir)/<(addon_target_name).node',
+          ],
+        },
+      ], # end actions
+    }, # end target copy_addon
+  ], # end targets
+}
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/docs/repl.txt b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/docs/repl.txt
new file mode 100644
index 000000000000..b334900c183a
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/docs/repl.txt
@@ -0,0 +1,81 @@
+
+{{alias}}( x, μ, λ )
+    Evaluates the natural logarithm of the probability density function
+    (PDF) for a Wald distribution with mean `μ` and shape parameter `λ` at a
+    value `x`.
+
+    If provided `NaN` as any argument, the function returns `NaN`.
+
+    If provided `μ <= 0`, the function returns `NaN`.
+
+    If provided `λ < 0`, the function returns `NaN`.
+
+    Parameters
+    ----------
+    x: number
+        Input value.
+
+    μ: number
+        Mean parameter.
+
+    λ: number
+        Shape parameter.
+
+    Returns
+    -------
+    out: number
+        Evaluated logPDF.
+
+    Examples
+    --------
+    > var y = {{alias}}( 2.0, 1.0, 1.0 )
+    ~-2.209
+    > y = {{alias}}( 0.5, 2.0, 3.0 )
+    ~-1.017
+    > y = {{alias}}( -1.0, 4.0, 2.0 )
+    -Infinity
+    > y = {{alias}}( NaN, 1.0, 1.0 )
+    NaN
+    > y = {{alias}}( 0.0, NaN, 1.0 )
+    NaN
+    > y = {{alias}}( 0.0, 1.0, NaN )
+    NaN
+    // Negative shape parameter:
+    > y = {{alias}}( 2.0, 1.0, -1.0 )
+    NaN
+    // Degenerate distribution when `λ = 0.0`:
+    > y = {{alias}}( 2.0, 8.0, 0.0 )
+    -Infinity
+    > y = {{alias}}( 8.0, 8.0, 0.0 )
+    Infinity
+    > y = {{alias}}( 10.0, 8.0, 0.0 )
+    -Infinity
+
+
+{{alias}}.factory( μ, λ )
+    Returns a function for evaluating the natural logarithm of the probability
+    density function (PDF) of a Wald distribution with mean `μ` and shape
+    parameter `λ`.
+
+    Parameters
+    ----------
+    μ: number
+        Mean parameter.
+
+    λ: number
+        Shape parameter.
+
+    Returns
+    -------
+    logpdf: Function
+        Logarithm of probability density function (PDF).
+
+    Examples
+    --------
+    > var mylogpdf = {{alias}}.factory( 10.0, 2.0 );
+    > var y = mylogpdf( 10.0 )
+    ~-4.026
+
+    See Also
+    --------
+
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/docs/types/index.d.ts b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/docs/types/index.d.ts
new file mode 100644
index 000000000000..d492aa4d097d
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/docs/types/index.d.ts
@@ -0,0 +1,121 @@
+/*
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+// TypeScript Version: 4.1
+
+/**
+* Evaluates the natural logarithm of the probability density function (PDF) for a Wald distribution.
+*
+* @param x - input value
+* @returns evaluated logPDF
+*/
+type Unary = ( x: number ) => number;
+
+/**
+* Interface for the natural logarithm of the probability density function (PDF) of a Wald distribution.
+*/
+interface LogPDF {
+	/**
+	* Evaluates the natural logarithm of the probability density function (PDF) for a Wald distribution with mean `mu` and shape parameter `lambda` at a value `x`.
+	*
+	* ## Notes
+	*
+	* -   If provided `mu <= 0` or `lambda < 0`, the function returns `NaN`.
+	*
+	* @param x - input value
+	* @param mu - mean
+	* @param lambda - shape parameter
+	* @returns evaluated logPDF
+	*
+	* @example
+	* var y = logpdf( 2.0, 1.0, 1.0 );
+	* // returns ~-2.209
+	*
+	* @example
+	* var y = logpdf( 0.5, 2.0, 3.0 );
+	* // returns ~-1.017
+	*
+	* @example
+	* var y = logpdf( NaN, 1.0, 1.0 );
+	* // returns NaN
+	*
+	* @example
+	* var y = logpdf( 0.0, NaN, 1.0 );
+	* // returns NaN
+	*
+	* @example
+	* var y = logpdf( 0.0, 1.0, NaN );
+	* // returns NaN
+	*
+	* @example
+	* // Nonpositive mean:
+	* var y = logpdf( 2.0, 0.0, 1.0 );
+	* // returns NaN
+	*
+	* @example
+	* // Negative shape parameter:
+	* var y = logpdf( 2.0, 1.0, -1.0 );
+	* // returns NaN
+	*
+	* @example
+	* // Degenerate distribution when `lambda = 0.0`:
+	* var y = logpdf( 2.0, 8.0, 0.0 );
+	* // returns -Infinity
+	*/
+	( x: number, mu: number, lambda: number ): number;
+
+	/**
+	* Returns a function for evaluating the natural logarithm of the probability density function (PDF) for a Wald distribution.
+	*
+	* @param mu - mean
+	* @param lambda - shape parameter
+	* @returns function to evaluate the natural logarithm of the probability density function
+	*
+	* @example
+	* var mylogpdf = logpdf.factory( 10.0, 2.0 );
+	* var y = mylogpdf( 10.0 );
+	* // returns ~-4.026
+	*
+	* y = mylogpdf( 12.0 );
+	* // returns ~-4.303
+	*/
+	factory( mu: number, lambda: number ): Unary;
+}
+
+/**
+* Wald distribution natural logarithm of the probability density function (PDF).
+*
+* @param x - input value
+* @param mu - mean
+* @param lambda - shape parameter
+* @returns evaluated logPDF
+*
+* @example
+* var y = logpdf( 2.0, 1.0, 1.0 );
+* // returns ~-2.209
+*
+* var mylogpdf = logpdf.factory( 10.0, 2.0 );
+* y = mylogpdf( 10.0 );
+* // returns ~-4.026
+*/
+declare var logpdf: LogPDF;
+
+
+// EXPORTS //
+
+export = logpdf;
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/docs/types/test.ts b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/docs/types/test.ts
new file mode 100644
index 000000000000..d3dd8d5a61ba
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/docs/types/test.ts
@@ -0,0 +1,119 @@
+/*
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+import logpdf = require( './index' );
+
+
+// TESTS //
+
+// The function returns a number...
+{
+	logpdf( 2, 2, 4 ); // $ExpectType number
+	logpdf( 1, 2, 8 ); // $ExpectType number
+}
+
+// The compiler throws an error if the function is provided values other than three numbers...
+{
+	logpdf( true, 3, 6 ); // $ExpectError
+	logpdf( false, 2, 4 ); // $ExpectError
+	logpdf( '5', 1, 2 ); // $ExpectError
+	logpdf( [], 1, 2 ); // $ExpectError
+	logpdf( {}, 2, 4 ); // $ExpectError
+	logpdf( ( x: number ): number => x, 2, 4 ); // $ExpectError
+
+	logpdf( 9, true, 12 ); // $ExpectError
+	logpdf( 9, false, 12 ); // $ExpectError
+	logpdf( 5, '5', 10 ); // $ExpectError
+	logpdf( 8, [], 16 ); // $ExpectError
+	logpdf( 9, {}, 18 ); // $ExpectError
+	logpdf( 8, ( x: number ): number => x, 16 ); // $ExpectError
+
+	logpdf( 9, 5, true ); // $ExpectError
+	logpdf( 9, 5, false ); // $ExpectError
+	logpdf( 5, 2, '5' ); // $ExpectError
+	logpdf( 8, 4, [] ); // $ExpectError
+	logpdf( 9, 4, {} ); // $ExpectError
+	logpdf( 8, 5, ( x: number ): number => x ); // $ExpectError
+}
+
+// The compiler throws an error if the function is provided an unsupported number of arguments...
+{
+	logpdf(); // $ExpectError
+	logpdf( 2 ); // $ExpectError
+	logpdf( 2, 0 ); // $ExpectError
+	logpdf( 2, 0, 4, 1 ); // $ExpectError
+}
+
+// Attached to main export is a `factory` method which returns a function...
+{
+	logpdf.factory( 3, 4 ); // $ExpectType Unary
+}
+
+// The `factory` method returns a function which returns a number...
+{
+	const fcn = logpdf.factory( 3, 4 );
+	fcn( 2 ); // $ExpectType number
+}
+
+// The compiler throws an error if the function returned by the `factory` method is provided invalid arguments...
+{
+	const fcn = logpdf.factory( 3, 4 );
+	fcn( true ); // $ExpectError
+	fcn( false ); // $ExpectError
+	fcn( '5' ); // $ExpectError
+	fcn( [] ); // $ExpectError
+	fcn( {} ); // $ExpectError
+	fcn( ( x: number ): number => x ); // $ExpectError
+}
+
+// The compiler throws an error if the function returned by the `factory` method is provided an unsupported number of arguments...
+{
+	const fcn = logpdf.factory( 3, 4 );
+	fcn(); // $ExpectError
+	fcn( 2, 0 ); // $ExpectError
+	fcn( 2, 0, 1 ); // $ExpectError
+}
+
+// The compiler throws an error if the `factory` method is provided values other than two numbers...
+{
+	logpdf.factory( true, 3 ); // $ExpectError
+	logpdf.factory( false, 2 ); // $ExpectError
+	logpdf.factory( '5', 1 ); // $ExpectError
+	logpdf.factory( [], 1 ); // $ExpectError
+	logpdf.factory( {}, 2 ); // $ExpectError
+	logpdf.factory( ( x: number ): number => x, 2 ); // $ExpectError
+
+	logpdf.factory( 9, true ); // $ExpectError
+	logpdf.factory( 9, false ); // $ExpectError
+	logpdf.factory( 5, '5' ); // $ExpectError
+	logpdf.factory( 8, [] ); // $ExpectError
+	logpdf.factory( 9, {} ); // $ExpectError
+	logpdf.factory( 8, ( x: number ): number => x ); // $ExpectError
+
+	logpdf.factory( [], true ); // $ExpectError
+	logpdf.factory( {}, false ); // $ExpectError
+	logpdf.factory( false, '5' ); // $ExpectError
+	logpdf.factory( {}, [] ); // $ExpectError
+	logpdf.factory( '5', ( x: number ): number => x ); // $ExpectError
+}
+
+// The compiler throws an error if the `factory` method is provided an unsupported number of arguments...
+{
+	logpdf.factory( 0 ); // $ExpectError
+	logpdf.factory( 0, 4, 8 ); // $ExpectError
+}
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/examples/c/Makefile b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/examples/c/Makefile
new file mode 100644
index 000000000000..c8f8e9a1517b
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/examples/c/Makefile
@@ -0,0 +1,146 @@
+#/
+# @license Apache-2.0
+#
+# Copyright (c) 2026 The Stdlib Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#/
+
+# VARIABLES #
+
+ifndef VERBOSE
+	QUIET := @
+else
+	QUIET :=
+endif
+
+# Determine the OS ([1][1], [2][2]).
+#
+# [1]: https://en.wikipedia.org/wiki/Uname#Examples
+# [2]: http://stackoverflow.com/a/27776822/2225624
+OS ?= $(shell uname)
+ifneq (, $(findstring MINGW,$(OS)))
+	OS := WINNT
+else
+ifneq (, $(findstring MSYS,$(OS)))
+	OS := WINNT
+else
+ifneq (, $(findstring CYGWIN,$(OS)))
+	OS := WINNT
+else
+ifneq (, $(findstring Windows_NT,$(OS)))
+	OS := WINNT
+endif
+endif
+endif
+endif
+
+# Define the program used for compiling C source files:
+ifdef C_COMPILER
+	CC := $(C_COMPILER)
+else
+	CC := gcc
+endif
+
+# Define the command-line options when compiling C files:
+CFLAGS ?= \
+	-std=c99 \
+	-O3 \
+	-Wall \
+	-pedantic
+
+# Determine whether to generate position independent code ([1][1], [2][2]).
+#
+# [1]: https://gcc.gnu.org/onlinedocs/gcc/Code-Gen-Options.html#Code-Gen-Options
+# [2]: http://stackoverflow.com/questions/5311515/gcc-fpic-option
+ifeq ($(OS), WINNT)
+	fPIC ?=
+else
+	fPIC ?= -fPIC
+endif
+
+# List of includes (e.g., `-I /foo/bar -I /beep/boop/include`):
+INCLUDE ?=
+
+# List of source files:
+SOURCE_FILES ?=
+
+# List of libraries (e.g., `-lopenblas -lpthread`):
+LIBRARIES ?=
+
+# List of library paths (e.g., `-L /foo/bar -L /beep/boop`):
+LIBPATH ?=
+
+# List of C targets:
+c_targets := example.out
+
+
+# RULES #
+
+#/
+# Compiles source files.
+#
+# @param {string} [C_COMPILER] - C compiler (e.g., `gcc`)
+# @param {string} [CFLAGS] - C compiler options
+# @param {(string|void)} [fPIC] - compiler flag determining whether to generate position independent code (e.g., `-fPIC`)
+# @param {string} [INCLUDE] - list of includes (e.g., `-I /foo/bar -I /beep/boop/include`)
+# @param {string} [SOURCE_FILES] - list of source files
+# @param {string} [LIBPATH] - list of library paths (e.g., `-L /foo/bar -L /beep/boop`)
+# @param {string} [LIBRARIES] - list of libraries (e.g., `-lopenblas -lpthread`)
+#
+# @example
+# make
+#
+# @example
+# make all
+#/
+all: $(c_targets)
+
+.PHONY: all
+
+#/
+# Compiles C source files.
+#
+# @private
+# @param {string} CC - C compiler (e.g., `gcc`)
+# @param {string} CFLAGS - C compiler options
+# @param {(string|void)} fPIC - compiler flag determining whether to generate position independent code (e.g., `-fPIC`)
+# @param {string} INCLUDE - list of includes (e.g., `-I /foo/bar`)
+# @param {string} SOURCE_FILES - list of source files
+# @param {string} LIBPATH - list of library paths (e.g., `-L /foo/bar`)
+# @param {string} LIBRARIES - list of libraries (e.g., `-lopenblas`)
+#/
+$(c_targets): %.out: %.c
+	$(QUIET) $(CC) $(CFLAGS) $(fPIC) $(INCLUDE) -o $@ $(SOURCE_FILES) $< $(LIBPATH) -lm $(LIBRARIES)
+
+#/
+# Runs compiled examples.
+#
+# @example
+# make run
+#/
+run: $(c_targets)
+	$(QUIET) ./$<
+
+.PHONY: run
+
+#/
+# Removes generated files.
+#
+# @example
+# make clean
+#/
+clean:
+	$(QUIET) -rm -f *.o *.out
+
+.PHONY: clean
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/examples/c/example.c b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/examples/c/example.c
new file mode 100644
index 000000000000..d86c86571f9d
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/examples/c/example.c
@@ -0,0 +1,44 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+#include "stdlib/stats/base/dists/wald/logpdf.h"
+#include "stdlib/constants/float64/eps.h"
+#include <stdlib.h>
+#include <stdio.h>
+#include <time.h>
+
+static double random_uniform( const double min, const double max ) {
+	double v = (double)rand() / ( (double)RAND_MAX + 1.0 );
+	return min + ( v*(max-min) );
+}
+
+int main( void ) {
+	double lambda;
+	double mu;
+	double x;
+	double y;
+	int i;
+
+	for ( i = 0; i < 10; i++ ) {
+		x = random_uniform( STDLIB_CONSTANT_FLOAT64_EPS, 10.0 );
+		mu = random_uniform( STDLIB_CONSTANT_FLOAT64_EPS, 10.0 );
+		lambda = random_uniform( STDLIB_CONSTANT_FLOAT64_EPS, 10.0 );
+		y = stdlib_base_dists_wald_logpdf( x, mu, lambda );
+		printf( "x: %lf, μ: %lf, λ: %lf, ln(f(x;μ,λ)): %lf\n", x, mu, lambda, y );
+	}
+}
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/examples/index.js b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/examples/index.js
new file mode 100644
index 000000000000..41dcac2d4cc7
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/examples/index.js
@@ -0,0 +1,33 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+var uniform = require( '@stdlib/random/array/uniform' );
+var logEachMap = require( '@stdlib/console/log-each-map' );
+var EPS = require( '@stdlib/constants/float64/eps' );
+var logpdf = require( './../lib' );
+
+var opts = {
+	'dtype': 'float64'
+};
+var x = uniform( 10, EPS, 10.0, opts );
+var mu = uniform( 10, EPS, 10.0, opts );
+var lambda = uniform( 10, EPS, 20.0, opts );
+
+logEachMap( 'x: %0.4f, μ: %0.4f, λ: %0.4f, ln(f(x;μ,λ)): %0.4f', x, mu, lambda, logpdf );
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/include.gypi b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/include.gypi
new file mode 100644
index 000000000000..bee8d41a2caf
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/include.gypi
@@ -0,0 +1,53 @@
+# @license Apache-2.0
+#
+# Copyright (c) 2026 The Stdlib Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# A GYP include file for building a Node.js native add-on.
+#
+# Main documentation:
+#
+# [1]: https://gyp.gsrc.io/docs/InputFormatReference.md
+# [2]: https://gyp.gsrc.io/docs/UserDocumentation.md
+{
+  # Define variables to be used throughout the configuration for all targets:
+  'variables': {
+    # Source directory:
+    'src_dir': './src',
+
+    # Include directories:
+    'include_dirs': [
+      '<!@(node -e "var arr = require(\'@stdlib/utils/library-manifest\')(\'./manifest.json\',{},{\'basedir\':process.cwd(),\'paths\':\'posix\'}).include; for ( var i = 0; i < arr.length; i++ ) { console.log( arr[ i ] ); }")',
+    ],
+
+    # Add-on destination directory:
+    'addon_output_dir': './src',
+
+    # Source files:
+    'src_files': [
+      '<(src_dir)/addon.c',
+      '<!@(node -e "var arr = require(\'@stdlib/utils/library-manifest\')(\'./manifest.json\',{},{\'basedir\':process.cwd(),\'paths\':\'posix\'}).src; for ( var i = 0; i < arr.length; i++ ) { console.log( arr[ i ] ); }")',
+    ],
+
+    # Library dependencies:
+    'libraries': [
+      '<!@(node -e "var arr = require(\'@stdlib/utils/library-manifest\')(\'./manifest.json\',{},{\'basedir\':process.cwd(),\'paths\':\'posix\'}).libraries; for ( var i = 0; i < arr.length; i++ ) { console.log( arr[ i ] ); }")',
+    ],
+
+    # Library directories:
+    'library_dirs': [
+      '<!@(node -e "var arr = require(\'@stdlib/utils/library-manifest\')(\'./manifest.json\',{},{\'basedir\':process.cwd(),\'paths\':\'posix\'}).libpath; for ( var i = 0; i < arr.length; i++ ) { console.log( arr[ i ] ); }")',
+    ],
+  }, # end variables
+}
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/include/stdlib/stats/base/dists/wald/logpdf.h b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/include/stdlib/stats/base/dists/wald/logpdf.h
new file mode 100644
index 000000000000..4f995631fe38
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/include/stdlib/stats/base/dists/wald/logpdf.h
@@ -0,0 +1,38 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+#ifndef STDLIB_STATS_BASE_DISTS_WALD_LOGPDF_H
+#define STDLIB_STATS_BASE_DISTS_WALD_LOGPDF_H
+
+/*
+* If C++, prevent name mangling so that the compiler emits a binary file having undecorated names, thus mirroring the behavior of a C compiler.
+*/
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+* Evaluates the natural logarithm of the probability density function (PDF) for a Wald distribution with mean `mu` and shape parameter `lambda` at a value `x`.
+*/
+double stdlib_base_dists_wald_logpdf( const double x, const double mu, const double lambda );
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // !STDLIB_STATS_BASE_DISTS_WALD_LOGPDF_H
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/lib/factory.js b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/lib/factory.js
new file mode 100644
index 000000000000..359d8ab9191a
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/lib/factory.js
@@ -0,0 +1,90 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var constantFunction = require( '@stdlib/utils/constant-function' );
+var degenerate = require( '@stdlib/stats/base/dists/degenerate/logpdf' ).factory;
+var isnan = require( '@stdlib/math/base/assert/is-nan' );
+var ln = require( '@stdlib/math/base/special/ln' );
+var LN_TWO_PI = require( '@stdlib/constants/float64/ln-two-pi' );
+var PINF = require( '@stdlib/constants/float64/pinf' );
+var NINF = require( '@stdlib/constants/float64/ninf' );
+
+
+// MAIN //
+
+/**
+* Returns a function for evaluating the natural logarithm of the probability density function (PDF) for a Wald distribution.
+*
+* @param {PositiveNumber} mu - mean
+* @param {NonNegativeNumber} lambda - shape parameter
+* @returns {Function} function to evaluate the natural logarithm of the probability density function
+*
+* @example
+* var logpdf = factory( 1.0, 1.0 );
+* var y = logpdf( 2.0 );
+* // returns ~-2.209
+*
+* y = logpdf( 0.5 );
+* // returns ~-0.129
+*/
+function factory( mu, lambda ) {
+	if (
+		isnan( mu ) ||
+		isnan( lambda ) ||
+		mu <= 0.0 ||
+		lambda < 0.0
+	) {
+		return constantFunction( NaN );
+	}
+	if ( lambda === 0.0 ) {
+		return degenerate( mu );
+	}
+	return logpdf;
+
+	/**
+	* Evaluates the natural logarithm of the probability density function (PDF) of a Wald distribution.
+	*
+	* @private
+	* @param {number} x - input value
+	* @returns {number} evaluated logPDF
+	*
+	* @example
+	* var y = logpdf( 2.0 );
+	* // returns <number>
+	*/
+	function logpdf( x ) {
+		var v;
+		if ( isnan( x ) ) {
+			return NaN;
+		}
+		if ( x <= 0.0 || x === PINF ) {
+			return NINF;
+		}
+		v = x - mu;
+		return 0.5 * ( ln( lambda ) - ( LN_TWO_PI + ( 3.0 * ln( x ) ) ) - ( ( lambda * v * v ) / ( mu * mu * x ) ) );
+	}
+}
+
+
+// EXPORTS //
+
+module.exports = factory;
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/lib/index.js b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/lib/index.js
new file mode 100644
index 000000000000..f48cdf6e1d20
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/lib/index.js
@@ -0,0 +1,51 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+/**
+* Wald distribution logarithm of probability density function (PDF).
+*
+* @module @stdlib/stats/base/dists/wald/logpdf
+*
+* @example
+* var logpdf = require( '@stdlib/stats/base/dists/wald/logpdf' );
+*
+* var y = logpdf( 2.0, 1.0, 1.0 );
+* // returns ~-2.209
+*
+* var mylogpdf = logpdf.factory( 2.0, 1.0 );
+* y = mylogpdf( 2.0 );
+* // returns ~-1.959
+*/
+
+// MODULES //
+
+var setReadOnly = require( '@stdlib/utils/define-nonenumerable-read-only-property' );
+var main = require( './main.js' );
+var factory = require( './factory.js' );
+
+
+// MAIN //
+
+setReadOnly( main, 'factory', factory );
+
+
+// EXPORTS //
+
+module.exports = main;
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/lib/main.js b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/lib/main.js
new file mode 100644
index 000000000000..f56813ff4d81
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/lib/main.js
@@ -0,0 +1,103 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var isnan = require( '@stdlib/math/base/assert/is-nan' );
+var ln = require( '@stdlib/math/base/special/ln' );
+var LN_TWO_PI = require( '@stdlib/constants/float64/ln-two-pi' );
+var PINF = require( '@stdlib/constants/float64/pinf' );
+var NINF = require( '@stdlib/constants/float64/ninf' );
+
+
+// MAIN //
+
+/**
+* Evaluates the natural logarithm of the probability density function (PDF) for a Wald distribution with mean `mu` and shape parameter `lambda` at a value `x`.
+*
+* @param {number} x - input value
+* @param {PositiveNumber} mu - mean
+* @param {NonNegativeNumber} lambda - shape parameter
+* @returns {number} evaluated logPDF
+*
+* @example
+* var y = logpdf( 2.0, 1.0, 1.0 );
+* // returns ~-2.209
+*
+* @example
+* var y = logpdf( 0.5, 2.0, 3.0 );
+* // returns ~-1.017
+*
+* @example
+* var y = logpdf( NaN, 1.0, 1.0 );
+* // returns NaN
+*
+* @example
+* var y = logpdf( 1.0, NaN, 1.0 );
+* // returns NaN
+*
+* @example
+* var y = logpdf( 1.0, 1.0, NaN );
+* // returns NaN
+*
+* @example
+* // Non-positive mean:
+* var y = logpdf( 2.0, 0.0, 1.0 );
+* // returns NaN
+*
+* @example
+* // Negative shape parameter:
+* var y = logpdf( 2.0, 1.0, -1.0 );
+* // returns NaN
+*
+* @example
+* // Zero shape parameter (degenerate distribution):
+* var y = logpdf( 1.0, 1.0, 0.0 );
+* // returns Infinity
+*
+* @example
+* var y = logpdf( 0.0, 1.0, 1.0 );
+* // returns -Infinity
+*/
+function logpdf( x, mu, lambda ) {
+	var v;
+	if (
+		isnan( x ) ||
+		isnan( mu ) ||
+		isnan( lambda ) ||
+		mu <= 0.0 ||
+		lambda < 0.0
+	) {
+		return NaN;
+	}
+	if ( lambda === 0.0 ) {
+		return ( x === mu ) ? PINF : NINF;
+	}
+	if ( x <= 0.0 || x === PINF ) {
+		return NINF;
+	}
+	v = x - mu;
+	return 0.5 * ( ln( lambda ) - ( LN_TWO_PI + ( 3.0 * ln( x ) ) ) - ( ( lambda * v * v ) / ( mu * mu * x ) ) );
+}
+
+
+// EXPORTS //
+
+module.exports = logpdf;
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/lib/native.js b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/lib/native.js
new file mode 100644
index 000000000000..bd6c0d3d4ab9
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/lib/native.js
@@ -0,0 +1,83 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var addon = require( './../src/addon.node' );
+
+
+// MAIN //
+
+/**
+* Evaluates the natural logarithm of the probability density function (PDF) for a Wald distribution with mean `mu` and shape parameter `lambda` at a value `x`.
+*
+* @private
+* @param {number} x - input value
+* @param {PositiveNumber} mu - mean
+* @param {number} lambda - shape parameter
+* @returns {number} evaluated logPDF
+*
+* @example
+* var y = logpdf( 2.0, 1.0, 1.0 );
+* // returns ~-2.209
+*
+* @example
+* var y = logpdf( 0.5, 2.0, 3.0 );
+* // returns ~-1.017
+*
+* @example
+* var y = logpdf( NaN, 1.0, 1.0 );
+* // returns NaN
+*
+* @example
+* var y = logpdf( 1.0, NaN, 1.0 );
+* // returns NaN
+*
+* @example
+* var y = logpdf( 1.0, 1.0, NaN );
+* // returns NaN
+*
+* @example
+* // Non-positive mean:
+* var y = logpdf( 2.0, 0.0, 1.0 );
+* // returns NaN
+*
+* @example
+* // Negative shape parameter:
+* var y = logpdf( 2.0, 1.0, -1.0 );
+* // returns NaN
+*
+* @example
+* // Zero shape parameter (degenerate distribution):
+* var y = logpdf( 1.0, 1.0, 0.0 );
+* // returns Infinity
+*
+* @example
+* var y = logpdf( 0.0, 1.0, 1.0 );
+* // returns -Infinity
+*/
+function logpdf( x, mu, lambda ) {
+	return addon( x, mu, lambda );
+}
+
+
+// EXPORTS //
+
+module.exports = logpdf;
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/manifest.json b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/manifest.json
new file mode 100644
index 000000000000..4bd5a6fbe257
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/manifest.json
@@ -0,0 +1,90 @@
+{
+  "options": {
+    "task": "build",
+    "wasm": false
+  },
+  "fields": [
+    {
+      "field": "src",
+      "resolve": true,
+      "relative": true
+    },
+    {
+      "field": "include",
+      "resolve": true,
+      "relative": true
+    },
+    {
+      "field": "libraries",
+      "resolve": false,
+      "relative": false
+    },
+    {
+      "field": "libpath",
+      "resolve": true,
+      "relative": false
+    }
+  ],
+  "confs": [
+    {
+      "task": "build",
+      "wasm": false,
+      "src": [
+        "./src/main.c"
+      ],
+      "include": [
+        "./include"
+      ],
+      "libraries": [],
+      "libpath": [],
+      "dependencies": [
+        "@stdlib/math/base/napi/ternary",
+        "@stdlib/math/base/assert/is-nan",
+        "@stdlib/math/base/special/ln",
+        "@stdlib/constants/float64/ln-two-pi",
+        "@stdlib/constants/float64/pinf",
+        "@stdlib/constants/float64/ninf"
+      ]
+    },
+    {
+      "task": "benchmark",
+      "wasm": false,
+      "src": [
+        "./src/main.c"
+      ],
+      "include": [
+        "./include"
+      ],
+      "libraries": [],
+      "libpath": [],
+      "dependencies": [
+        "@stdlib/math/base/assert/is-nan",
+        "@stdlib/math/base/special/ln",
+        "@stdlib/constants/float64/ln-two-pi",
+        "@stdlib/constants/float64/pinf",
+        "@stdlib/constants/float64/ninf",
+        "@stdlib/constants/float64/eps"
+      ]
+    },
+    {
+      "task": "examples",
+      "wasm": false,
+      "src": [
+        "./src/main.c"
+      ],
+      "include": [
+        "./include"
+      ],
+      "libraries": [],
+      "libpath": [],
+      "dependencies": [
+        "@stdlib/math/base/assert/is-nan",
+        "@stdlib/math/base/special/ln",
+        "@stdlib/constants/float64/ln-two-pi",
+        "@stdlib/constants/float64/pinf",
+        "@stdlib/constants/float64/ninf",
+        "@stdlib/constants/float64/eps"
+      ]
+    }
+  ]
+}
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/package.json b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/package.json
new file mode 100644
index 000000000000..ef6c7d5143c7
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/package.json
@@ -0,0 +1,73 @@
+{
+  "name": "@stdlib/stats/base/dists/wald/logpdf",
+  "version": "0.0.0",
+  "description": "Natural logarithm of the probability density function (PDF) for a Wald distribution.",
+  "license": "Apache-2.0",
+  "author": {
+    "name": "The Stdlib Authors",
+    "url": "https://github.com/stdlib-js/stdlib/graphs/contributors"
+  },
+  "contributors": [
+    {
+      "name": "The Stdlib Authors",
+      "url": "https://github.com/stdlib-js/stdlib/graphs/contributors"
+    }
+  ],
+  "main": "./lib",
+  "gypfile": true,
+  "directories": {
+    "benchmark": "./benchmark",
+    "doc": "./docs",
+    "example": "./examples",
+    "include": "./include",
+    "lib": "./lib",
+    "src": "./src",
+    "test": "./test"
+  },
+  "types": "./docs/types",
+  "scripts": {},
+  "homepage": "https://github.com/stdlib-js/stdlib",
+  "repository": {
+    "type": "git",
+    "url": "git://github.com/stdlib-js/stdlib.git"
+  },
+  "bugs": {
+    "url": "https://github.com/stdlib-js/stdlib/issues"
+  },
+  "dependencies": {},
+  "devDependencies": {},
+  "engines": {
+    "node": ">=0.10.0",
+    "npm": ">2.7.0"
+  },
+  "os": [
+    "aix",
+    "darwin",
+    "freebsd",
+    "linux",
+    "macos",
+    "openbsd",
+    "sunos",
+    "win32",
+    "windows"
+  ],
+  "keywords": [
+    "stdlib",
+    "stdmath",
+    "statistics",
+    "stats",
+    "distribution",
+    "dist",
+    "probability",
+    "pdf",
+    "logpdf",
+    "density",
+    "density function",
+    "logarithm",
+    "inverse gaussian",
+    "inverse-gaussian",
+    "wald",
+    "univariate",
+    "continuous"
+  ]
+}
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/src/Makefile b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/src/Makefile
new file mode 100644
index 000000000000..2caf905cedbe
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/src/Makefile
@@ -0,0 +1,70 @@
+#/
+# @license Apache-2.0
+#
+# Copyright (c) 2026 The Stdlib Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#/
+
+# VARIABLES #
+
+ifndef VERBOSE
+	QUIET := @
+else
+	QUIET :=
+endif
+
+# Determine the OS ([1][1], [2][2]).
+#
+# [1]: https://en.wikipedia.org/wiki/Uname#Examples
+# [2]: http://stackoverflow.com/a/27776822/2225624
+OS ?= $(shell uname)
+ifneq (, $(findstring MINGW,$(OS)))
+	OS := WINNT
+else
+ifneq (, $(findstring MSYS,$(OS)))
+	OS := WINNT
+else
+ifneq (, $(findstring CYGWIN,$(OS)))
+	OS := WINNT
+else
+ifneq (, $(findstring Windows_NT,$(OS)))
+	OS := WINNT
+endif
+endif
+endif
+endif
+
+
+# RULES #
+
+#/
+# Removes generated files for building an add-on.
+#
+# @example
+# make clean-addon
+#/
+clean-addon:
+	$(QUIET) -rm -f *.o *.node
+
+.PHONY: clean-addon
+
+#/
+# Removes generated files.
+#
+# @example
+# make clean
+#/
+clean: clean-addon
+
+.PHONY: clean
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/src/addon.c b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/src/addon.c
new file mode 100644
index 000000000000..3424f34bd62a
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/src/addon.c
@@ -0,0 +1,22 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+#include "stdlib/stats/base/dists/wald/logpdf.h"
+#include "stdlib/math/base/napi/ternary.h"
+
+STDLIB_MATH_BASE_NAPI_MODULE_DDD_D( stdlib_base_dists_wald_logpdf )
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/src/main.c b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/src/main.c
new file mode 100644
index 000000000000..6f980ed3e03a
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/src/main.c
@@ -0,0 +1,58 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+#include "stdlib/stats/base/dists/wald/logpdf.h"
+#include "stdlib/math/base/assert/is_nan.h"
+#include "stdlib/math/base/special/ln.h"
+#include "stdlib/constants/float64/ln_two_pi.h"
+#include "stdlib/constants/float64/pinf.h"
+#include "stdlib/constants/float64/ninf.h"
+
+/**
+* Evaluates the natural logarithm of the probability density function (PDF) for a Wald distribution with mean `mu` and shape parameter `lambda` at a value `x`.
+*
+* @param x         input value
+* @param mu        mean
+* @param lambda    shape parameter
+* @return          evaluated logPDF
+*
+* @example
+* double y = stdlib_base_dists_wald_logpdf( 2.0, 1.0, 1.0 );
+* // returns ~-2.209
+*/
+double stdlib_base_dists_wald_logpdf( const double x, const double mu, const double lambda ) {
+	double v;
+
+	if (
+		stdlib_base_is_nan( x ) ||
+		stdlib_base_is_nan( mu ) ||
+		stdlib_base_is_nan( lambda ) ||
+		mu <= 0.0 ||
+		lambda < 0.0
+	) {
+		return 0.0 / 0.0; // NaN
+	}
+	if ( lambda == 0.0 ) {
+		return ( x == mu ) ? STDLIB_CONSTANT_FLOAT64_PINF : STDLIB_CONSTANT_FLOAT64_NINF;
+	}
+	if ( x <= 0.0 || x == STDLIB_CONSTANT_FLOAT64_PINF ) {
+		return STDLIB_CONSTANT_FLOAT64_NINF;
+	}
+	v = x - mu;
+	return 0.5 * ( stdlib_base_ln( lambda ) - ( STDLIB_CONSTANT_FLOAT64_LN_TWO_PI + ( 3.0 * stdlib_base_ln( x ) ) ) - ( ( lambda * v * v ) / ( mu * mu * x ) ) );
+}
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/fixtures/julia/REQUIRE b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/fixtures/julia/REQUIRE
new file mode 100644
index 000000000000..98be20b58ed3
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/fixtures/julia/REQUIRE
@@ -0,0 +1,3 @@
+Distributions 0.23.8
+julia 1.5
+JSON 0.21
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/fixtures/julia/data.json b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/fixtures/julia/data.json
new file mode 100644
index 000000000000..af645789b732
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/fixtures/julia/data.json
@@ -0,0 +1 @@
+{"expected":[-1.807356083766194,-3.7661876830471717,-4.09713952499646,-4.759875657168522,-1.435126244867679,-16.106102316430118,-3.5208010885749395,-4.6532484952404145,-3.9705125997818618,-4.731760216344789,-6.434275471300456,-3.930158626753529,-6.779220239094343,-4.769728385385832,-2.7090028005277293,-5.774116869662516,-3.8473949774033795,-1.3341796455155586,-3.399972265790514,-4.482601656535909,-2.7875520402374185,-1.9988705978491446,-4.546287907509452,-4.173410287832915,-4.434652718779226,-4.6570700428119105,-8.115448060901599,-2.673045062561434,-2.2376587054617714,-1.9822173136487486,-3.4139941507376554,-3.7060180924212696,-5.831901695256952,-3.410607071572126,-3.6488818569286052,-3.6046283842273574,-7.9478216935434745,-3.2165468646198776,-4.242523409247204,-1.5916372201464113,-3.078503363560462,-4.1129148038845615,-3.071257898639816,-3.7468156802413772,-4.128905023648782,-3.6666440527105593,-5.006424962458075,-4.870331584287318,-3.811441550441342,-3.8179639625980424,-4.492214719853926,-4.066358920385641,-2.221836410791899,-4.344237015730915,-5.865207986933859,-3.304487030353284,-2.962458872609372,-4.379261380826107,-1.5534406469448974,-5.541273973165811,-1.5358219992492863,-3.458192854155716,-2.119164060705691,-4.173383337179523,-1.5992318279489712,-5.521480875603727,-4.991650820085336,-3.569375315389194,-2.411455262394331,-2.3515691537828567,-3.424106071201136,-3.8160964981177554,-4.051705076848215,-2.2575151677186254,-3.846422441477871,-4.027576013880456,-1.776626180739711,-27.21179071242486,-5.643471706543188,-3.3760613154288452,-14.687664843959805,-3.539747703695054,-0.49282525156488555,-2.015042532620259,-1.996186513545724,-4.390160437755958,-8.337066318522536,-8.308429197681814,-3.874084653389918,-3.722499338080903,-5.463946601644408,-3.7984665113559326,-4.732499909224339,-2.305379177092935,-4.522220397929102,-5.34010790085401,-0.5047024576196902,-1.8880394072051447,-4.170591799956805,-8.40802666226443],"lambda":[2.0829780438523584,0.788907128812072,0.5826502094988851,0.9721255686101145,2.020432143043645,3.018307030660872,2.006869344300821,2.2022445556748886,0.727341999866994,0.9765600363108202,3.7627741407380433,3.1922707138048603,3.674457614801312,2.7772363489845686,4.181275984054642,2.2776056027422222,5.489907609816406,5.441388113344254,5.470206185697659,3.3889697837781867,1.1401322980733826,2.7627937417264943,2.2524588602360485,5.3014497413613615,3.856388882907787,1.2710760932100869,1.1112024981174264,1.9816031978517707,5.171772717386017,3.8034600449409086,4.760080771219022,1.604557701358534,1.2733675539669487,4.335883274471257,1.3986353010990822,2.1194909193500795,3.62985934370937,3.0825208253988308,2.7467678008483247,3.2199558674952358,1.5168342429393162,4.146350531099111,2.3061044907784094,2.443858700792048,4.357298768198664,2.068019582062124,0.8148320122801662,2.0405077322363434,4.444833310471711,2.553262439265859,4.732912191058152,0.6117839818626221,2.999565405234149,2.899310024112763,4.957139712891404,1.7508514525157832,1.3084022581265877,4.395145146161421,4.084011425310193,2.66011547049649,2.620457038240386,2.529892602007581,2.4301217459075612,2.455774125489231,5.11381643736844,0.9254570870204022,3.1864837549071705,1.8515788200851375,2.073533381124295,4.913262047558962,1.9876693411997677,1.3002216632116803,1.8462432401630164,4.5746152786971805,2.3503458821358,4.729319495474027,1.7016281735168306,5.048222406832838,2.1721232506085535,4.456945118492067,4.307459697650853,1.4868522257332262,2.9523430791772767,5.22062131730879,1.4442888866046366,0.5775533131284145,2.2473154515946248,1.8382838399540542,3.399759857747699,2.022013686153964,2.3651643880557063,3.1499185329405432,1.1568521200736415,4.942645117699139,2.461220955553476,1.1855235852543684,4.512101035468202,1.888274489844044,4.53217853652334,2.6910847663058552],"mu":[2.705237690570664,2.0174185780538507,4.417259267740106,8.11891999203111,6.178756905960784,1.0632565759477515,3.8105702759192788,3.564024081250132,5.447388409031971,7.070987346686483,2.2364258830406767,6.837012896133256,1.991731815145717,1.7237895391234188,5.092679884031784,1.423750955246907,5.8635279772478786,3.720313000116036,7.008589520428778,8.406632072798587,7.338859663851698,4.935112916816286,3.6961735784164933,7.674104304299979,7.726989404662392,1.2105227320374718,0.9698475188861895,6.782276075147356,8.678096295599731,9.53183814495321,9.49577690159986,4.496437906106843,2.386848587695935,5.610148555537841,7.937922064133462,3.2496812036224663,1.426129410893719,4.309878423785049,6.491257694247297,8.660354708596122,2.836328503943237,6.166297598480408,2.416601854085255,1.7097289582798032,10.029057080236784,10.179938830987073,8.515524448890524,4.1516779754854465,7.041293012179984,3.6988612193791734,4.092013386101564,8.329848314190336,6.307429014985896,2.5428293703708587,2.0966709881458687,7.676191873374184,1.1573758635074256,6.576032336457545,3.626464297908541,3.4970166228592356,9.78121926483119,9.182356712432584,7.447023634537737,3.101451644430602,3.5305529245756224,2.064015394005236,3.1271574996548908,6.779999122170629,5.596291764936209,5.181625640055231,7.230624442446645,6.543239585065949,5.956977016530007,5.919825419002402,4.46811141593913,3.086206781032314,9.253407837164355,1.1000442580720022,2.4164332491515568,10.077099434346303,0.9388582399014374,10.341401932289752,1.3225452186660565,6.144427539482325,6.734786455990657,7.486865822204306,1.1549852068187123,1.7271123117967997,7.981817033600624,3.5209311084887966,2.7332305896316162,4.1284402781605865,8.874680593439903,5.973217503081442,4.714281127005082,3.6124732477482198,1.3335169945054755,2.9840768863904996,9.72611298310989,1.0579872988825152],"x":[2.2929635764394347,5.382691519258584,6.888942297260575,12.718088941088066,1.2824888081653363,11.109735091063529,6.740275544960681,11.455919428090947,6.8612040729196835,12.41609496320854,10.909138434072561,10.62908655149402,10.146404129292808,6.370627669761742,5.310926809721271,6.8044592940375574,10.95650786032364,1.6542913692430372,9.05481028384292,15.367015603287474,3.5267671359094797,2.684009525007249,11.17610861515396,14.0088116968333,15.118471390167379,5.282677724788488,8.63015579067391,3.9256122719296958,3.492601395573761,0.7424532211306801,8.870063168231834,7.295510762296818,13.993647708357887,8.257437909127617,6.893814090846924,6.799596705772302,7.747337928114624,6.469558014970721,12.128906323767566,1.0739539270874432,4.6392348233914635,12.140369804993643,4.764210128678875,4.933531814762607,13.687396911709108,7.922625518545036,14.131051917259073,13.626554586545689,10.863381413567739,8.126185346686302,11.54971736167793,6.914612521611113,3.1823810784990645,8.009714306849368,8.241126032116671,5.880460361188619,2.97522060822683,14.287392932662257,2.2282185498050993,15.446681652794261,0.6663897122189256,7.3727145802564245,2.631006648457358,8.69571958476866,2.5868120012691973,11.753293747434382,11.483885528233369,7.185014604970533,3.334172571684492,4.3787014111985805,6.675975309457076,7.520736793030265,9.662483466812127,3.8636429315753364,8.647305569908605,8.04279467338117,1.6900780340901234,13.244116775228921,11.873235308043416,8.427609338387212,6.525107336621665,6.480288544072877,1.0307966435527152,3.165931741252435,2.0741401944664823,8.421658020022289,7.773777252730126,15.031921631578331,10.655394530426864,7.353281665295917,12.42189371229788,8.643769631836154,13.248342299218448,4.133462822881555,12.47909935781141,15.363599290845745,1.247410432371154,2.3276779417607747,14.146211886306677,6.285842982964795]}
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/fixtures/julia/runner.jl b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/fixtures/julia/runner.jl
new file mode 100644
index 000000000000..272494b63bad
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/fixtures/julia/runner.jl
@@ -0,0 +1,78 @@
+#!/usr/bin/env julia
+#
+# @license Apache-2.0
+#
+# Copyright (c) 2026 The Stdlib Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import Distributions: logpdf, InverseGaussian
+import JSON
+
+"""
+	gen( x, mu, lambda, name )
+
+Generate fixture data and write to file.
+
+# Arguments
+
+* `x`: input value
+* `mu`: mean
+* `lambda`: shape parameter
+* `name::AbstractString`: output filename
+
+# Examples
+
+``` julia
+julia> x = rand( 100 ) .* 15.0 .+ 0.5;
+julia> mu = rand( 100 ) .* 10.0 .+ 0.5;
+julia> lambda = rand( 100 ) .* 5.0 .+ 0.5;
+julia> gen( x, mu, lambda, "data.json" );
+```
+"""
+function gen( x, mu, lambda, name )
+	z = Array{Float64}( undef, length(x) );
+	for i in eachindex(x)
+		z[ i ] = logpdf( InverseGaussian( mu[i], lambda[i] ), x[i] );
+	end
+
+	# Store data to be written to file as a collection:
+	data = Dict([
+		("x", x),
+		("mu", mu),
+		("lambda", lambda),
+		("expected", z)
+	]);
+
+	# Based on the script directory, create an output filepath:
+	filepath = joinpath( dir, name );
+
+	# Write the data to the output filepath as JSON:
+	outfile = open( filepath, "w" );
+	write( outfile, JSON.json(data) );
+	write( outfile, "\n" );
+	close( outfile );
+end
+
+# Get the filename:
+file = @__FILE__;
+
+# Extract the directory in which this file resides:
+dir = dirname( file );
+
+# Generate fixtures:
+x = rand( 100 ) .* 15.0 .+ 0.5;
+mu = rand( 100 ) .* 10.0 .+ 0.5;
+lambda = rand( 100 ) .* 5.0 .+ 0.5;
+gen( x, mu, lambda, "data.json" );
+
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/test.factory.js b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/test.factory.js
new file mode 100644
index 000000000000..b88c7c6f4625
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/test.factory.js
@@ -0,0 +1,198 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var tape = require( 'tape' );
+var isnan = require( '@stdlib/math/base/assert/is-nan' );
+var isAlmostSameValue = require( '@stdlib/assert/is-almost-same-value' );
+var PINF = require( '@stdlib/constants/float64/pinf' );
+var NINF = require( '@stdlib/constants/float64/ninf' );
+var factory = require( './../lib/factory.js' );
+
+
+// FIXTURES //
+
+var data = require( './fixtures/julia/data.json' );
+
+
+// TESTS //
+
+tape( 'main export is a function', function test( t ) {
+	t.ok( true, __filename );
+	t.strictEqual( typeof factory, 'function', 'main export is a function' );
+	t.end();
+});
+
+tape( 'the function returns a function', function test( t ) {
+	var logpdf = factory( 1.0, 1.0 );
+	t.strictEqual( typeof logpdf, 'function', 'returns expected value' );
+	t.end();
+});
+
+tape( 'if provided `NaN` for any parameter, the created function returns `NaN`', function test( t ) {
+	var logpdf;
+	var y;
+
+	logpdf = factory( 1.0, 1.0 );
+	y = logpdf( NaN );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	logpdf = factory( NaN, 1.0 );
+	y = logpdf( 0.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	logpdf = factory( 1.0, NaN );
+	y = logpdf( 0.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	logpdf = factory( NaN, NaN );
+	y = logpdf( 0.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	logpdf = factory( NaN, NaN );
+	y = logpdf( NaN );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'if provided a valid `mu` and `lambda`, the function returns a function which returns `-infinity` when provided `+infinity` for `x`', function test( t ) {
+	var logpdf;
+	var y;
+
+	logpdf = factory( 1.0, 0.0 );
+	y = logpdf( PINF );
+	t.strictEqual( y, NINF, 'returns expected value' );
+
+	logpdf = factory( 1.0, 1.0 );
+	y = logpdf( PINF );
+	t.strictEqual( y, NINF, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'if provided a valid `mu` and `lambda`, the function returns a function which returns `-infinity` when provided `-infinity` for `x`', function test( t ) {
+	var logpdf;
+	var y;
+
+	logpdf = factory( 1.0, 0.0 );
+	y = logpdf( NINF );
+	t.strictEqual( y, NINF, 'returns expected value' );
+
+	logpdf = factory( 1.0, 1.0 );
+	y = logpdf( NINF );
+	t.strictEqual( y, NINF, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'if provided a nonpositive `mu`, the created function always returns `NaN`', function test( t ) {
+	var logpdf;
+	var y;
+
+	logpdf = factory( 0.0, 1.0 );
+	y = logpdf( 2.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	logpdf = factory( -1.0, 1.0 );
+	y = logpdf( 2.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	logpdf = factory( NINF, 1.0 );
+	y = logpdf( 2.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'if provided a negative `lambda`, the created function always returns `NaN`', function test( t ) {
+	var logpdf;
+	var y;
+
+	logpdf = factory( 0.0, -1.0 );
+
+	y = logpdf( 2.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	y = logpdf( 0.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	logpdf = factory( 0.0, NINF );
+	y = logpdf( 2.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	logpdf = factory( PINF, NINF );
+	y = logpdf( 2.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	logpdf = factory( NINF, NINF );
+	y = logpdf( 2.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	logpdf = factory( NaN, NINF );
+	y = logpdf( 2.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'if `lambda` equals `0`, the created function evaluates a degenerate distribution centered at `mu`', function test( t ) {
+	var logpdf;
+	var y;
+
+	logpdf = factory( 2.0, 0.0 );
+
+	y = logpdf( 2.0 );
+	t.strictEqual( y, PINF, 'returns expected value' );
+
+	y = logpdf( 3.0 );
+	t.strictEqual( y, NINF, 'returns expected value' );
+
+	y = logpdf( 1.0 );
+	t.strictEqual( y, NINF, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'the function evaluates the logpdf for `x` given parameters `mu` and `lambda`', function test( t ) {
+	var expected;
+	var lambda;
+	var logpdf;
+	var mu;
+	var x;
+	var y;
+	var i;
+
+	expected = data.expected;
+	x = data.x;
+	mu = data.mu;
+	lambda = data.lambda;
+	for ( i = 0; i < x.length; i++ ) {
+		logpdf = factory( mu[i], lambda[i] );
+		y = logpdf( x[i] );
+		if ( y === expected[i] ) {
+			t.strictEqual( y, expected[i], 'x: '+x[i]+', mu:'+mu[i]+', lambda: '+lambda[i]+', y: '+y+', expected: '+expected[i] );
+		} else {
+			t.ok( isAlmostSameValue( y, expected[ i ], 2 ), 'within tolerance. x: '+x[ i ]+'. mu: '+mu[i]+'. lambda: '+lambda[i]+'. y: '+y+'. E: '+expected[ i ]+'.' );
+		}
+	}
+	t.end();
+});
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/test.js b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/test.js
new file mode 100644
index 000000000000..c8fb79a7c82a
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/test.js
@@ -0,0 +1,38 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var tape = require( 'tape' );
+var logpdf = require( './../lib' );
+
+
+// TESTS //
+
+tape( 'main export is a function', function test( t ) {
+	t.ok( true, __filename );
+	t.strictEqual( typeof logpdf, 'function', 'main export is a function' );
+	t.end();
+});
+
+tape( 'attached to the main export is a factory method for generating `logpdf` functions', function test( t ) {
+	t.strictEqual( typeof logpdf.factory, 'function', 'exports a factory method' );
+	t.end();
+});
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/test.main.js b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/test.main.js
new file mode 100644
index 000000000000..e4e298f48c8b
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/test.main.js
@@ -0,0 +1,149 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var tape = require( 'tape' );
+var isnan = require( '@stdlib/math/base/assert/is-nan' );
+var isAlmostSameValue = require( '@stdlib/assert/is-almost-same-value' );
+var PINF = require( '@stdlib/constants/float64/pinf' );
+var NINF = require( '@stdlib/constants/float64/ninf' );
+var logpdf = require( './../lib' );
+
+
+// FIXTURES //
+
+var data = require( './fixtures/julia/data.json' );
+
+
+// TESTS //
+
+tape( 'main export is a function', function test( t ) {
+	t.ok( true, __filename );
+	t.strictEqual( typeof logpdf, 'function', 'main export is a function' );
+	t.end();
+});
+
+tape( 'if provided `NaN` for any parameter, the function returns `NaN`', function test( t ) {
+	var y = logpdf( NaN, 1.0, 1.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+	y = logpdf( 0.0, NaN, 1.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+	y = logpdf( 0.0, 1.0, NaN );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+	t.end();
+});
+
+tape( 'if provided a nonpositive `mu`, the function always returns `NaN`', function test( t ) {
+	var y;
+
+	y = logpdf( 2.0, 0.0, 1.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	y = logpdf( 2.0, -1.0, 1.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	y = logpdf( 2.0, NINF, 1.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'if provided `+infinity` for `x` and a valid `mu` and `lambda`, the function returns `-infinity`', function test( t ) {
+	var y = logpdf( PINF, 1.0, 0.0 );
+	t.strictEqual( y, NINF, 'returns expected value' );
+
+	y = logpdf( PINF, 1.0, 1.0 );
+	t.strictEqual( y, NINF, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'if provided `-infinity` for `x` and a valid `mu` and `lambda`, the function returns `-infinity`', function test( t ) {
+	var y = logpdf( NINF, 1.0, 0.0 );
+	t.strictEqual( y, NINF, 'returns expected value' );
+
+	y = logpdf( NINF, 1.0, 1.0 );
+	t.strictEqual( y, NINF, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'if provided a negative `lambda`, the function always returns `NaN`', function test( t ) {
+	var y;
+
+	y = logpdf( 2.0, 0.0, -1.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	y = logpdf( 0.0, 0.0, -1.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	y = logpdf( 2.0, 0.0, NINF );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	y = logpdf( 2.0, PINF, NINF );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	y = logpdf( 2.0, NINF, NINF );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	y = logpdf( 2.0, NaN, NINF );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'if provided `lambda` equals `0`, the function evaluates a degenerate distribution centered at `mu`', function test( t ) {
+	var y;
+
+	y = logpdf( 2.0, 2.0, 0.0 );
+	t.strictEqual( y, PINF, 'returns +infinity for x equal to mu' );
+
+	y = logpdf( 3.0, 2.0, 0.0 );
+	t.strictEqual( y, NINF, 'returns -infinity for x greater than mu' );
+
+	y = logpdf( 1.0, 2.0, 0.0 );
+	t.strictEqual( y, NINF, 'returns -infinity for x smaller than mu' );
+
+	t.end();
+});
+
+tape( 'the function evaluates the logpdf for `x` given parameters `mu` and `lambda`', function test( t ) {
+	var expected;
+	var lambda;
+	var mu;
+	var i;
+	var x;
+	var y;
+
+	expected = data.expected;
+	x = data.x;
+	mu = data.mu;
+	lambda = data.lambda;
+	for ( i = 0; i < x.length; i++ ) {
+		y = logpdf( x[i], mu[i], lambda[i] );
+		if ( y === expected[i] ) {
+			t.strictEqual( y, expected[i], 'x: '+x[i]+', mu: '+mu[i]+', lambda: '+lambda[i]+', y: '+y+', expected: '+expected[i] );
+		} else {
+			t.ok( isAlmostSameValue( y, expected[ i ], 2 ), 'within tolerance. x: '+x[ i ]+'. mu: '+mu[i]+'. lambda: '+lambda[i]+'. y: '+y+'. E: '+expected[ i ]+'.' );
+		}
+	}
+	t.end();
+});
diff --git a/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/test.native.js b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/test.native.js
new file mode 100644
index 000000000000..b1036c7e5935
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/base/dists/wald/logpdf/test/test.native.js
@@ -0,0 +1,158 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var resolve = require( 'path' ).resolve;
+var tape = require( 'tape' );
+var tryRequire = require( '@stdlib/utils/try-require' );
+var isnan = require( '@stdlib/math/base/assert/is-nan' );
+var isAlmostSameValue = require( '@stdlib/assert/is-almost-same-value' );
+var PINF = require( '@stdlib/constants/float64/pinf' );
+var NINF = require( '@stdlib/constants/float64/ninf' );
+
+
+// FIXTURES //
+
+var data = require( './fixtures/julia/data.json' );
+
+
+// VARIABLES //
+
+var logpdf = tryRequire( resolve( __dirname, './../lib/native.js' ) );
+var opts = {
+	'skip': ( logpdf instanceof Error )
+};
+
+
+// TESTS //
+
+tape( 'main export is a function', opts, function test( t ) {
+	t.ok( true, __filename );
+	t.strictEqual( typeof logpdf, 'function', 'main export is a function' );
+	t.end();
+});
+
+tape( 'if provided `NaN` for any parameter, the function returns `NaN`', opts, function test( t ) {
+	var y = logpdf( NaN, 1.0, 1.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+	y = logpdf( 0.0, NaN, 1.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+	y = logpdf( 0.0, 1.0, NaN );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+	t.end();
+});
+
+tape( 'if provided a nonpositive `mu`, the function always returns `NaN`', opts, function test( t ) {
+	var y;
+
+	y = logpdf( 2.0, 0.0, 1.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	y = logpdf( 2.0, -1.0, 1.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	y = logpdf( 2.0, NINF, 1.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'if provided `+infinity` for `x` and a valid `mu` and `lambda`, the function returns `-infinity`', opts, function test( t ) {
+	var y = logpdf( PINF, 1.0, 0.0 );
+	t.strictEqual( y, NINF, 'returns expected value' );
+
+	y = logpdf( PINF, 1.0, 1.0 );
+	t.strictEqual( y, NINF, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'if provided `-infinity` for `x` and a valid `mu` and `lambda`, the function returns `-infinity`', opts, function test( t ) {
+	var y = logpdf( NINF, 1.0, 0.0 );
+	t.strictEqual( y, NINF, 'returns expected value' );
+
+	y = logpdf( NINF, 1.0, 1.0 );
+	t.strictEqual( y, NINF, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'if provided a negative `lambda`, the function always returns `NaN`', opts, function test( t ) {
+	var y;
+
+	y = logpdf( 2.0, 0.0, -1.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	y = logpdf( 0.0, 0.0, -1.0 );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	y = logpdf( 2.0, 0.0, NINF );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	y = logpdf( 2.0, PINF, NINF );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	y = logpdf( 2.0, NINF, NINF );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	y = logpdf( 2.0, NaN, NINF );
+	t.strictEqual( isnan( y ), true, 'returns expected value' );
+
+	t.end();
+});
+
+tape( 'if provided `lambda` equals `0`, the function evaluates a degenerate distribution centered at `mu`', opts, function test( t ) {
+	var y;
+
+	y = logpdf( 2.0, 2.0, 0.0 );
+	t.strictEqual( y, PINF, 'returns +infinity for x equal to mu' );
+
+	y = logpdf( 3.0, 2.0, 0.0 );
+	t.strictEqual( y, NINF, 'returns -infinity for x greater than mu' );
+
+	y = logpdf( 1.0, 2.0, 0.0 );
+	t.strictEqual( y, NINF, 'returns -infinity for x smaller than mu' );
+
+	t.end();
+});
+
+tape( 'the function evaluates the logpdf for `x` given parameters `mu` and `lambda`', opts, function test( t ) {
+	var expected;
+	var lambda;
+	var mu;
+	var x;
+	var y;
+	var i;
+
+	expected = data.expected;
+	x = data.x;
+	mu = data.mu;
+	lambda = data.lambda;
+	for ( i = 0; i < x.length; i++ ) {
+		y = logpdf( x[i], mu[i], lambda[i] );
+		if ( y === expected[i] ) {
+			t.strictEqual( y, expected[i], 'x: '+x[i]+', mu:'+mu[i]+', lambda: '+lambda[i]+', y: '+y+', expected: '+expected[i] );
+		} else {
+			t.ok( isAlmostSameValue( y, expected[ i ], 2 ), 'within tolerance. x: '+x[ i ]+'. mu: '+mu[i]+'. lambda: '+lambda[i]+'. y: '+y+'. E: '+expected[ i ]+'.' );
+		}
+	}
+	t.end();
+});