diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumprod/README.md b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/README.md
new file mode 100644
index 000000000000..051bfcaf08de
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/README.md
@@ -0,0 +1,177 @@
+
+
+# incrnanmsumprod
+
+> Compute a moving sum of products incrementally, ignoring `NaN` values.
+
+
+
+For a window of size `W`, the moving sum of products is defined as
+
+
+
+```math
+s = \sum_{i=0}^{W-1} x_i y_i
+```
+
+
+
+
+
+
+
+
+
+
+
+## Usage
+
+```javascript
+var incrnanmsumprod = require( '@stdlib/stats/incr/nanmsumprod' );
+```
+
+#### incrnanmsumprod( window )
+
+Returns an accumulator function which incrementally computes a moving sum of products. The `window` parameter defines the number of values over which to compute the moving sum of products, ignoring `NaN` values.
+
+```javascript
+var accumulator = incrnanmsumprod( 4 );
+```
+
+#### accumulator( \[x, y] )
+
+If provided input values `x` and `y`, the accumulator function returns an updated sum. If not provided input values `x` and `y`, the accumulator function returns the current sum.
+
+```javascript
+var accumulator = incrnanmsumprod( 3 );
+
+var sum = accumulator();
+// returns null
+
+// Fill the window...
+sum = accumulator( 2.0, 3.0 ); // [(2.0,3.0)]
+// returns 6.0
+
+sum = accumulator( 1.0, -1.0 ); // [(2.0,3.0), (1.0,-1.0)]
+// returns 5.0
+
+sum = accumulator( NaN, -1.0 );
+// returns 5.0
+
+sum = accumulator( -3.0, 5.0 ); // [(2.0,3.0), (1.0,-1.0), (-3.0,5.0)]
+// returns -10.0
+
+// Window begins sliding...
+sum = accumulator( -7.0, -1.0 ); // [(1.0,-1.0), (-3.0,5.0), (-7.0,-1.0)]
+// returns -9.0
+
+sum = accumulator( 5.0, 4.0 ); // [(-3.0,5.0), (-7.0,-1.0), (5.0,4.0)]
+// returns 12.0
+
+sum = accumulator( 5.0, NaN );
+// returns 12.0
+
+sum = accumulator();
+// returns 12.0
+```
+
+
+
+
+
+
+
+## Notes
+
+- Input values are **not** type checked. If non-numeric inputs are possible, you are advised to type check and handle accordingly **before** passing the value to the accumulator function.
+- As `W` (x,y) pairs are needed to fill the window buffer, the first `W-1` returned values are calculated from smaller sample sizes. Until the window is full, each returned value is calculated from all provided values.
+
+
+
+
+
+
+
+## Examples
+
+
+
+```javascript
+var randu = require( '@stdlib/random/base/randu' );
+var isnan = require( '@stdlib/math/base/assert/is-nan' );
+var incrnanmsumprod = require( '@stdlib/stats/incr/nanmsumprod' );
+
+// Initialize an accumulator:
+var accumulator = incrnanmsumprod( 5 );
+
+// For each simulated datum, update the moving sum-product...
+console.log( '\nValue\tValue\tSum\n' );
+var v1;
+var v2;
+var i;
+for ( i = 0; i < 100; i++ ) {
+ v1 = ( randu() < 0.2 ) ? NaN : randu() * 100.0;
+ v2 = ( randu() < 0.2 ) ? NaN : randu() * 100.0;
+ accumulator( v1, v2 );
+}
+console.log( accumulator() );
+```
+
+
+
+
+
+
+
+
+
+* * *
+
+## See Also
+
+- [`@stdlib/stats/incr/mprod`][@stdlib/stats/incr/mprod]: compute a moving product incrementally.
+- [`@stdlib/stats/incr/msum`][@stdlib/stats/incr/msum]: compute a moving sum incrementally.
+- [`@stdlib/stats/incr/sumprod`][@stdlib/stats/incr/sumprod]: compute a sum of products incrementally.
+
+
+
+
+
+
+
+
+
+
+
+[@stdlib/stats/incr/mprod]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/stats/incr/mprod
+
+[@stdlib/stats/incr/msum]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/stats/incr/msum
+
+[@stdlib/stats/incr/sumprod]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/stats/incr/sumprod
+
+
+
+
+
+
diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumprod/benchmark/benchmark.js b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/benchmark/benchmark.js
new file mode 100644
index 000000000000..f7c20662a117
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/benchmark/benchmark.js
@@ -0,0 +1,68 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2025 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 pkg = require( './../package.json' ).name;
+var incrmsumprod = require( './../lib' );
+
+
+// MAIN //
+
+bench( pkg, function benchmark( b ) {
+ var f;
+ var i;
+ b.tic();
+ for ( i = 0; i < b.iterations; i++ ) {
+ f = incrmsumprod( (i%5)+1 );
+ if ( typeof f !== 'function' ) {
+ b.fail( 'should return a function' );
+ }
+ }
+ b.toc();
+ if ( typeof f !== 'function' ) {
+ b.fail( 'should return a function' );
+ }
+ b.pass( 'benchmark finished' );
+ b.end();
+});
+
+bench( pkg+'::accumulator', function benchmark( b ) {
+ var acc;
+ var v;
+ var i;
+
+ acc = incrmsumprod( 5 );
+
+ b.tic();
+ for ( i = 0; i < b.iterations; i++ ) {
+ v = acc( i, i );
+ if ( v !== v ) {
+ b.fail( 'should not return NaN' );
+ }
+ }
+ b.toc();
+ if ( v !== v ) {
+ b.fail( 'should not return NaN' );
+ }
+ b.pass( 'benchmark finished' );
+ b.end();
+});
diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumprod/docs/img/equation_moving_sum_product.svg b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/docs/img/equation_moving_sum_product.svg
new file mode 100644
index 000000000000..2cdc3bec3c27
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/docs/img/equation_moving_sum_product.svg
@@ -0,0 +1,40 @@
+
\ No newline at end of file
diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumprod/docs/repl.txt b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/docs/repl.txt
new file mode 100644
index 000000000000..09575b649cb9
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/docs/repl.txt
@@ -0,0 +1,51 @@
+
+{{alias}}( W )
+ Returns an accumulator function which incrementally computes a moving sum of
+ products, ignoring `NaN` values.
+
+ The `W` parameter defines the number of (x,y) pairs over which to compute
+ the moving sum of products.
+
+ If provided input values, the accumulator function returns an updated moving
+ sum. If not provided input values, the accumulator function returns the
+ current moving sum.
+
+ As `W` (x,y) pairs are needed to fill the window buffer, the first `W-1`
+ returned values are calculated from smaller sample sizes. Until the window
+ is full, each returned value is calculated from all provided values.
+
+ Parameters
+ ----------
+ W: integer
+ Window size.
+
+ Returns
+ -------
+ acc: Function
+ Accumulator function.
+
+ Examples
+ --------
+ > var accumulator = {{alias}}( 3 );
+ > var s = accumulator()
+ null
+ > s = accumulator( 2.0, 3.0 )
+ 6.0
+ > s = accumulator( NaN, 3.0 )
+ 6.0
+ > s = accumulator( -5.0, 2.0 )
+ -4.0
+ > s = accumulator( -5.0, NaN )
+ -4.0
+ > s = accumulator( 3.0, -2.0 )
+ -10.0
+ > s = accumulator( NaN, NaN )
+ -10.0
+ > s = accumulator( 5.0, 3.0 )
+ -1.0
+ > s = accumulator()
+ -1.0
+
+ See Also
+ --------
+
diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumprod/docs/types/index.d.ts b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/docs/types/index.d.ts
new file mode 100644
index 000000000000..d6227de51c2e
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/docs/types/index.d.ts
@@ -0,0 +1,79 @@
+/*
+* @license Apache-2.0
+*
+* Copyright (c) 2025 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
+
+///
+
+/**
+* If provided arguments, returns an updated sum of products; otherwise, returns the current sum of products.
+*
+* @param x - value
+* @param y - value
+* @returns sum of products
+*/
+type accumulator = ( x?: number, y?: number ) => number | null;
+
+/**
+* Returns an accumulator function which incrementally computes a moving sum of products, ignoring `NaN` values.
+*
+* ## Notes
+*
+* - The `W` parameter defines the number of (x,y) pairs over which to compute the moving sum of products.
+* - As `W` (x,y) pairs are needed to fill the window buffer, the first `W-1` returned values are calculated from smaller sample sizes. Until the window is full, each returned value is calculated from all provided values.
+*
+* @param W - window size
+* @throws must provide a positive integer
+* @returns accumulator function
+*
+* @example
+* var accumulator = incrnanmsumprod( 3 );
+*
+* var sum = accumulator();
+* // returns null
+*
+* sum = accumulator( 2.0, 3.0 );
+* // returns 6.0
+*
+* sum = accumulator( NaN, 3.0 );
+* // returns 6.0
+*
+* sum = accumulator( -5.0, 2.0 );
+* // returns -4.0
+*
+* sum = accumulator( -5.0, NaN );
+* // returns -4.0
+*
+* sum = accumulator( 3.0, -2.0 );
+* // returns -10.0
+*
+* sum = accumulator( NaN, NaN );
+* // returns -10.0
+*
+* sum = accumulator( 5.0, 3.0 );
+* // returns -1.0
+*
+* sum = accumulator();
+* // returns -1.0
+*/
+declare function incrnanmsumprod( W: number ): accumulator;
+
+
+// EXPORTS //
+
+export = incrnanmsumprod;
diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumprod/docs/types/test.ts b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/docs/types/test.ts
new file mode 100644
index 000000000000..3558f25efdc7
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/docs/types/test.ts
@@ -0,0 +1,74 @@
+/*
+* @license Apache-2.0
+*
+* Copyright (c) 2025 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 incrnanmsumprod = require( './index' );
+
+
+// TESTS //
+
+// The function returns an accumulator function...
+{
+ incrnanmsumprod( 3 ); // $ExpectType accumulator
+}
+
+// The compiler throws an error if the function is provided an argument that is not a number...
+{
+ incrnanmsumprod( '5' ); // $ExpectError
+ incrnanmsumprod( true ); // $ExpectError
+ incrnanmsumprod( false ); // $ExpectError
+ incrnanmsumprod( null ); // $ExpectError
+ incrnanmsumprod( undefined ); // $ExpectError
+ incrnanmsumprod( [] ); // $ExpectError
+ incrnanmsumprod( {} ); // $ExpectError
+ incrnanmsumprod( ( x: number ): number => x ); // $ExpectError
+}
+
+// The compiler throws an error if the function is provided an invalid number of arguments...
+{
+ incrnanmsumprod(); // $ExpectError
+ incrnanmsumprod( 3, 5 ); // $ExpectError
+}
+
+// The function returns an accumulator function which returns an accumulated result...
+{
+ const acc = incrnanmsumprod( 3 );
+
+ acc(); // $ExpectType number | null
+ acc( 3.14, 2.0 ); // $ExpectType number | null
+}
+
+// The compiler throws an error if the returned accumulator function is provided invalid arguments...
+{
+ const acc = incrnanmsumprod( 3 );
+
+ acc( '5', 1.0 ); // $ExpectError
+ acc( true, 1.0 ); // $ExpectError
+ acc( false, 1.0 ); // $ExpectError
+ acc( null, 1.0 ); // $ExpectError
+ acc( [], 1.0 ); // $ExpectError
+ acc( {}, 1.0 ); // $ExpectError
+ acc( ( x: number ): number => x, 1.0 ); // $ExpectError
+
+ acc( 3.14, '5' ); // $ExpectError
+ acc( 3.14, true ); // $ExpectError
+ acc( 3.14, false ); // $ExpectError
+ acc( 3.14, null ); // $ExpectError
+ acc( 3.14, [] ); // $ExpectError
+ acc( 3.14, {} ); // $ExpectError
+ acc( 3.14, ( x: number ): number => x ); // $ExpectError
+}
diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumprod/examples/index.js b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/examples/index.js
new file mode 100644
index 000000000000..b440e28d3343
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/examples/index.js
@@ -0,0 +1,38 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2025 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 randu = require( '@stdlib/random/base/randu' );
+var incrnanmsumprod = require( './../lib' );
+
+// Initialize an accumulator:
+var accumulator = incrnanmsumprod( 5 );
+
+// For each simulated datum, update the moving sum-product...
+console.log( '\nValue\tValue\tSum\n' );
+var sum;
+var v1;
+var v2;
+var i;
+for ( i = 0; i < 100; i++ ) {
+ v1 = ( randu() < 0.2 ) ? NaN : randu() * 100.0;
+ v2 = ( randu() < 0.2 ) ? NaN : randu() * 100.0;
+ sum = accumulator( v1, v2 );
+ console.log( '%d\t%d\t%d', v1.toFixed( 4 ), v2.toFixed( 4 ), ( sum === null ) ? NaN : sum.toFixed( 4 ) );
+}
diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumprod/lib/index.js b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/lib/index.js
new file mode 100644
index 000000000000..6d8e4f7d5aee
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/lib/index.js
@@ -0,0 +1,66 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2025 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';
+
+/**
+* Compute a moving sum of products incrementally, ignoring `NaN` values.
+*
+* @module @stdlib/stats/incr/nanmsumprod
+*
+* @example
+* var incrnanmsumprod = require( '@stdlib/stats/incr/nanmsumprod' );
+*
+* var accumulator = incrnanmsumprod( 3 );
+*
+* var sum = accumulator();
+* // returns null
+*
+* sum = accumulator( 2.0, 3.0 );
+* // returns 6.0
+*
+* sum = accumulator( NaN, 3.0 );
+* // returns 6.0
+*
+* sum = accumulator( -5.0, 2.0 );
+* // returns -4.0
+*
+* sum = accumulator( -5.0, NaN );
+* // returns -4.0
+*
+* sum = accumulator( 3.0, -2.0 );
+* // returns -10.0
+*
+* sum = accumulator( NaN, NaN );
+* // returns -10.0
+*
+* sum = accumulator( 5.0, 3.0 );
+* // returns -1.0
+*
+* sum = accumulator();
+* // returns -1.0
+*/
+
+// MODULES //
+
+var main = require( './main.js' );
+
+
+// EXPORTS //
+
+module.exports = main;
diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumprod/lib/main.js b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/lib/main.js
new file mode 100644
index 000000000000..c32e084af6e0
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/lib/main.js
@@ -0,0 +1,91 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2025 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 incrmsum = require( '@stdlib/stats/incr/msumprod' );
+var isnan = require( '@stdlib/math/base/assert/is-nan' );
+
+
+// MAIN //
+
+/**
+* Returns an accumulator function which incrementally computes a moving sum of products, ignoring `NaN` values.
+*
+* @param {PositiveInteger} W - window size
+* @throws {TypeError} must provide a positive integer
+* @returns {Function} accumulator function
+*
+* @example
+* var accumulator = incrnanmsumprod( 3 );
+*
+* var sum = accumulator();
+* // returns null
+*
+* sum = accumulator( 2.0, 3.0 );
+* // returns 6.0
+*
+* sum = accumulator( NaN, 3.0 );
+* // returns 6.0
+*
+* sum = accumulator( -5.0, 2.0 );
+* // returns -4.0
+*
+* sum = accumulator( -5.0, NaN );
+* // returns -4.0
+*
+* sum = accumulator( 3.0, -2.0 );
+* // returns -10.0
+*
+* sum = accumulator( NaN, NaN );
+* // returns -10.0
+*
+* sum = accumulator( 5.0, 3.0 );
+* // returns -1.0
+*
+* sum = accumulator();
+* // returns -1.0
+*/
+function incrnanmsumprod( W ) {
+ var msumprod;
+
+ msumprod = incrmsum( W );
+ return accumulator;
+
+ /**
+ * If provided a value, the accumulator function returns an updated sum. If not provided a value, the accumulator function returns the current sum.
+ *
+ * @private
+ * @param {number} [x] - input value
+ * @param {number} [y] - input value
+ * @returns {(number|null)} sum or null
+ */
+ function accumulator( x, y ) {
+ if ( arguments.length === 0 || isnan( x ) || isnan( y ) ) {
+ return msumprod();
+ }
+ return msumprod( x, y );
+ }
+}
+
+
+// EXPORTS //
+
+module.exports = incrnanmsumprod;
diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumprod/package.json b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/package.json
new file mode 100644
index 000000000000..be3d42747c3f
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/package.json
@@ -0,0 +1,73 @@
+{
+ "name": "@stdlib/stats/incr/nanmsumprod",
+ "version": "0.0.0",
+ "description": "Compute a moving sum of products incrementally, ignoring `NaN` values.",
+ "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",
+ "directories": {
+ "benchmark": "./benchmark",
+ "doc": "./docs",
+ "example": "./examples",
+ "lib": "./lib",
+ "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",
+ "mathematics",
+ "math",
+ "sum",
+ "total",
+ "product",
+ "prod",
+ "dot",
+ "dot product",
+ "sum-product",
+ "incremental",
+ "accumulator",
+ "moving sum",
+ "sliding window",
+ "sliding",
+ "window",
+ "moving"
+ ]
+}
diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumprod/test/test.js b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/test/test.js
new file mode 100644
index 000000000000..952e6fe7bc22
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumprod/test/test.js
@@ -0,0 +1,147 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2025 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 incrnanmsumprod = require( '@stdlib/stats/incr/nanmsumprod/lib' );
+
+
+// TESTS //
+
+tape( 'main export is a function', function test( t ) {
+ t.ok( true, __filename );
+ t.strictEqual( typeof incrnanmsumprod, 'function', 'main export is a function' );
+ t.end();
+});
+
+tape( 'the function throws an error if not provided a positive integer', function test( t ) {
+ var values;
+ var i;
+
+ values = [
+ '5',
+ -5.0,
+ 0.0,
+ 3.14,
+ true,
+ null,
+ void 0,
+ NaN,
+ [],
+ {},
+ function noop() {}
+ ];
+
+ for ( i = 0; i < values.length; i++ ) {
+ t.throws( badValue( values[i] ), TypeError, 'throws an error when provided '+values[i] );
+ }
+ t.end();
+
+ function badValue( value ) {
+ return function badValue() {
+ incrnanmsumprod( value );
+ };
+ }
+});
+
+tape( 'the function returns an accumulator function', function test( t ) {
+ t.equal( typeof incrnanmsumprod( 3 ), 'function', 'returns a function' );
+ t.end();
+});
+
+tape( 'the accumulator function computes a moving sum of products incrementally', function test( t ) {
+ var expected;
+ var actual;
+ var data;
+ var acc;
+ var N;
+ var i;
+
+ data = [
+ [ 2.0, 3.0 ],
+ [ 3.0, -1.0 ],
+ [ 3.0, NaN ],
+ [ 2.0, 5.0 ],
+ [ NaN, 5.0 ],
+ [ 4.0, -4.0 ],
+ [ 3.0, 0.0 ],
+ [ NaN, NaN ],
+ [ -4.0, 5.0 ]
+ ];
+ N = data.length;
+
+ acc = incrnanmsumprod( 3 );
+
+ actual = [];
+ for ( i = 0; i < N; i++ ) {
+ actual.push( acc( data[ i ][ 0 ], data[ i ][ 1 ] ) );
+ }
+ expected = [ 6.0, 3.0, 3.0, 13.0, 13.0, -9.0, -6.0, -6.0, -36.0 ];
+
+ t.deepEqual( actual, expected, 'returns expected values' );
+ t.end();
+});
+
+tape( 'if not provided an input value, the accumulator function returns the current sum of products', function test( t ) {
+ var data;
+ var acc;
+ var i;
+
+ data = [
+ [ 2.0, 3.0 ],
+ [ 2.0, NaN ],
+ [ 3.0, -5.0 ],
+ [ NaN, 3.0 ],
+ [ NaN, NaN],
+ [ 1.0, 10.0 ]
+ ];
+ acc = incrnanmsumprod( 2 );
+ for ( i = 0; i < data.length; i++ ) {
+ acc( data[ i ][ 0 ], data[ i ][ 1 ] );
+ }
+ t.equal( acc(), -5.0, 'returns expected value' );
+ t.end();
+});
+
+tape( 'if data has yet to be provided, the accumulator function returns `null`', function test( t ) {
+ var acc = incrnanmsumprod( 3 );
+ t.equal( acc(), null, 'returns null' );
+ t.end();
+});
+
+tape( 'the accumulator function only provided `NaN` values returns `null` for the current sum of products', function test( t ) {
+ var data;
+ var acc;
+ var i;
+ data = [
+ [ 1.0, NaN ],
+ [ NaN, NaN ],
+ [ NaN, 4.0 ],
+ [ NaN, NaN ],
+ [ NaN, 2.0 ]
+ ];
+ acc = incrnanmsumprod( 3 );
+ for ( i = 0; i < data.length; i++ ) {
+ acc( data[ i ][ 0 ], data[ i ][ 1 ] );
+ }
+ t.equal( acc(), null, 'returns null' );
+ t.end();
+});