diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/README.md b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/README.md
new file mode 100644
index 000000000000..06b27f58d9d2
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/README.md
@@ -0,0 +1,180 @@
+
+
+# incrnanmsumabs2
+
+> Compute a moving sum of squared absolute values incrementally, ignoring NaN values.
+
+
+
+For a window of size `W`, the moving sum of squared absolute values is defined as
+
+
+
+```math
+s = \sum_{\substack{i=0\\x_i \neq \mathrm{NaN}}}^{W-1} x_i^2
+```
+
+
+
+
+
+
+
+
+
+
+
+## Usage
+
+```javascript
+var incrnanmsumabs2 = require( '@stdlib/stats/incr/nanmsumabs2' );
+```
+
+#### incrnanmsumabs2( window )
+
+Returns an accumulator `function` which incrementally computes a moving sum of squared absolute values, ignoring `NaN` values. The `window` parameter defines the number of values over which to compute the moving sum.
+
+```javascript
+var accumulator = incrnanmsumabs2( 3 );
+```
+
+#### accumulator( \[x] )
+
+If provided an input value `x`, the accumulator function returns an updated sum. If not provided an input value `x`, the accumulator function returns the current sum.
+
+```javascript
+var accumulator = incrnanmsumabs2( 3 );
+
+var sum = accumulator();
+// returns null
+
+// Fill the window...
+sum = accumulator( 2.0 ); // [2.0]
+// returns 4.0
+
+sum = accumulator( -1.0 ); // [2.0, -1.0]
+// returns 5.0
+
+sum = accumulator( NaN ); // [2.0, -1.0]
+// returns 5.0
+
+sum = accumulator( 3.0 ); // [2.0, -1.0, 3.0]
+// returns 14.0
+
+// Window begins sliding...
+sum = accumulator( -7.0 ); // [-1.0, 3.0, -7.0]
+// returns 59.0
+
+sum = accumulator( NaN ); // [3.0, -7.0]
+// returns 59.0
+
+sum = accumulator();
+// returns 59.0
+```
+
+
+
+
+
+
+
+## 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.
+- `NaN` values are ignored.
+- As `W` values (excluding `NaN` values) 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 (excluding `NaN` values).
+
+
+
+
+
+
+
+## Examples
+
+
+
+```javascript
+var randu = require( '@stdlib/random/base/randu' );
+var incrnanmsumabs2 = require( '@stdlib/stats/incr/nanmsumabs2' );
+
+var accumulator;
+var v;
+var i;
+
+// Initialize an accumulator:
+accumulator = incrnanmsumabs2( 5 );
+
+// For each simulated datum, update the moving sum...
+for ( i = 0; i < 100; i++ ) {
+ if ( randu() < 0.2 ) {
+ v = NaN;
+ } else {
+ v = ( randu()*100.0 ) - 50.0;
+ }
+ accumulator( v );
+}
+console.log( accumulator() );
+```
+
+
+
+
+
+
+
+
+
+* * *
+
+## See Also
+
+- [`@stdlib/stats/incr/msumabs2`][@stdlib/stats/incr/msumabs2]: compute a moving sum of squared absolute values incrementally.
+- [`@stdlib/stats/incr/nanmmeanabs2`][@stdlib/stats/incr/nanmmeanabs2]: compute a moving arithmetic mean of squared absolute values incrementally, ignoring NaN values.
+- [`@stdlib/stats/incr/nanmsumabs`][@stdlib/stats/incr/nanmsumabs]: compute a moving sum of absolute values incrementally, ignoring NaN values.
+- [`@stdlib/stats/incr/nansumabs2`][@stdlib/stats/incr/nansumabs2]: compute a sum of squared absolute values incrementally, ignoring NaN values.
+
+
+
+
+
+
+
+
+
+
+
+[@stdlib/stats/incr/msumabs2]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/stats/incr/msumabs2
+
+[@stdlib/stats/incr/nanmmeanabs2]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/stats/incr/nanmmeanabs2
+
+[@stdlib/stats/incr/nanmsumabs]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/stats/incr/nanmsumabs
+
+[@stdlib/stats/incr/nansumabs2]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/stats/incr/nansumabs2
+
+
+
+
+
+
diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/benchmark/benchmark.js b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/benchmark/benchmark.js
new file mode 100644
index 000000000000..d319f7bf589c
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/benchmark/benchmark.js
@@ -0,0 +1,69 @@
+/**
+* @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 randu = require( '@stdlib/random/base/randu' );
+var pkg = require( '@stdlib/stats/incr/nanmsumabs2/package.json' ).name;
+var incrnanmsumabs2 = require( '@stdlib/stats/incr/nanmsumabs2/lib' );
+
+
+// MAIN //
+
+bench( pkg, function benchmark( b ) {
+ var f;
+ var i;
+ b.tic();
+ for ( i = 0; i < b.iterations; i++ ) {
+ f = incrnanmsumabs2( (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 = incrnanmsumabs2( 5 );
+
+ b.tic();
+ for ( i = 0; i < b.iterations; i++ ) {
+ v = acc( randu()-0.5 );
+ 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/nanmsumabs2/docs/img/equation_moving_sum_squared_absolute_values.svg b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/docs/img/equation_moving_sum_squared_absolute_values.svg
new file mode 100644
index 000000000000..a550903e807e
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/docs/img/equation_moving_sum_squared_absolute_values.svg
@@ -0,0 +1,37 @@
+
\ No newline at end of file
diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/docs/repl.text b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/docs/repl.text
new file mode 100644
index 000000000000..f120e18f31b3
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/docs/repl.text
@@ -0,0 +1,47 @@
+{{alias}}( W )
+ Returns an accumulator function which incrementally computes a moving sum of
+ squared absolute values, ignoring NaN values.
+
+ The `W` parameter defines the number of values over which to compute the
+ moving sum.
+
+ If provided a value, the accumulator function returns an updated moving sum.
+ If not provided a value, the accumulator function returns the current moving
+ sum.
+
+ As `W` values 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.
+
+ NaN values are ignored. If the window consists solely of NaN values, the
+ function returns the current sum.
+
+ Parameters
+ ----------
+ W: integer
+ Window size.
+
+ Returns
+ -------
+ acc: Function
+ Accumulator function.
+
+ Examples
+ --------
+ > var accumulator = {{alias}}( 3 );
+ > var s = accumulator()
+ null
+ > s = accumulator( 2.0 )
+ 4.0
+ > s = accumulator( -5.0 )
+ 29.0
+ > s = accumulator( NaN )
+ 29.0
+ > s = accumulator( 3.0 )
+ 34.0
+ > s = accumulator()
+ 34.0
+
+ See Also
+ --------
+
diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/docs/types/index.d.ts b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/docs/types/index.d.ts
new file mode 100644
index 000000000000..a73f4c634246
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/docs/types/index.d.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.
+*/
+
+// TypeScript Version: 4.1
+
+///
+
+/**
+* If provided a value, returns an updated sum of squared absolute values; otherwise, returns the current sum of squared absolute values.
+*
+* ## Notes
+*
+* - NaN values are ignored.
+*
+* @param x - value
+* @returns sum of squared absolute values
+*/
+type accumulator = ( x?: number ) => number | null;
+
+/**
+* Returns an accumulator function which incrementally computes a moving sum of squared absolute values, ignoring NaN values.
+*
+* ## Notes
+*
+* - The `W` parameter defines the number of values over which to compute the moving sum.
+* - As `W` values 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.
+* - NaN values are ignored.
+*
+* @param W - window size
+* @throws must provide a positive integer
+* @returns accumulator function
+*
+* @example
+* var accumulator = incrnanmsumabs2( 3 );
+*
+* var sum = accumulator();
+* // returns null
+*
+* sum = accumulator( 2.0 );
+* // returns 4.0
+*
+* sum = accumulator( -5.0 );
+* // returns 29.0
+*
+* sum = accumulator( NaN );
+* // returns 29.0
+*
+* sum = accumulator( 3.0 );
+* // returns 34.0
+*
+* sum = accumulator();
+* // returns 34.0
+*/
+declare function incrnanmsumabs2( W: number ): accumulator;
+
+
+// EXPORTS //
+
+export = incrnanmsumabs2;
diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/docs/types/test.ts b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/docs/types/test.ts
new file mode 100644
index 000000000000..3116afbb680b
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/docs/types/test.ts
@@ -0,0 +1,60 @@
+/*
+* @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 incrnanmsumabs2 from './index';
+
+
+// TESTS //
+
+// The function returns an accumulator function...
+{
+ incrnanmsumabs2( 3 ); // $ExpectType accumulator
+}
+
+// The compiler throws an error if the function is provided an argument that is not a number...
+{
+ incrnanmsumabs2( '5' ); // $ExpectError
+ incrnanmsumabs2( true ); // $ExpectError
+ incrnanmsumabs2( false ); // $ExpectError
+ incrnanmsumabs2( null ); // $ExpectError
+ incrnanmsumabs2( undefined ); // $ExpectError
+ incrnanmsumabs2( [] ); // $ExpectError
+ incrnanmsumabs2( {} ); // $ExpectError
+ incrnanmsumabs2( ( x: number ): number => x ); // $ExpectError
+}
+
+// The function returns an accumulator function which returns an accumulated result...
+{
+ const acc = incrnanmsumabs2( 3 );
+
+ acc(); // $ExpectType number | null
+ acc( 3.14 ); // $ExpectType number | null
+}
+
+// The compiler throws an error if the returned function is provided invalid arguments...
+{
+ const acc = incrnanmsumabs2( 3 );
+
+ acc( '5' ); // $ExpectError
+ acc( true ); // $ExpectError
+ acc( false ); // $ExpectError
+ acc( null ); // $ExpectError
+ acc( [] ); // $ExpectError
+ acc( {} ); // $ExpectError
+ acc( ( x: number ): number => x ); // $ExpectError
+}
diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/examples/index.js b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/examples/index.js
new file mode 100644
index 000000000000..ebc3aa943da4
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/examples/index.js
@@ -0,0 +1,45 @@
+/**
+* @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 incrnanmsumabs2 = require( './../lib' );
+
+var accumulator;
+var sum;
+var v;
+var i;
+
+// Initialize an accumulator:
+accumulator = incrnanmsumabs2( 5 );
+
+// For each simulated datum, update the moving sum...
+
+console.log( '\nValue\tSum\n' );
+
+for ( i = 0; i < 100; i++ ) {
+ if ( randu() < 0.2 ) {
+ v = NaN;
+ } else {
+ v = ( randu() * 100.0 ) - 50.0;
+ }
+
+ sum = accumulator( v );
+ console.log( '%s\t%s', v.toString(), (sum) ? sum.toFixed(3) : 'null' );
+}
diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/lib/index.js b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/lib/index.js
new file mode 100644
index 000000000000..37a157db3e14
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/lib/index.js
@@ -0,0 +1,58 @@
+/**
+* @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 squared absolute values incrementally, ignoring NaN values.
+*
+* @module @stdlib/stats/incr/nanmsumabs2
+*
+* @example
+* var incrnanmsumabs2 = require( '@stdlib/stats/incr/nanmsumabs2' );
+*
+* var accumulator = incrnanmsumabs2( 3 );
+*
+* var sum = accumulator();
+* // returns null
+*
+* sum = accumulator( 2.0 );
+* // returns 4.0
+*
+* sum = accumulator( -5.0 );
+* // returns 29.0
+*
+* sum = accumulator( NaN );
+* // returns 29.0
+*
+* sum = accumulator( 3.0 );
+* // returns 34.0
+*
+* sum = accumulator();
+* // returns 34.0
+*/
+
+
+// MODULES //
+
+var incrnanmsumabs2 = require( './main.js' );
+
+
+// EXPORTS //
+
+module.exports = incrnanmsumabs2;
diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/lib/main.js b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/lib/main.js
new file mode 100644
index 000000000000..f5441ed15e99
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/lib/main.js
@@ -0,0 +1,88 @@
+/**
+* @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 isPositiveInteger = require( '@stdlib/assert/is-positive-integer' ).isPrimitive;
+var incrmsum = require( '@stdlib/stats/incr/msum' );
+var isnan = require( '@stdlib/math/base/assert/is-nan' );
+var format = require( '@stdlib/string/format' );
+
+
+// MAIN //
+
+/**
+* Returns an accumulator function which incrementally computes a moving sum of squared absolute values, ignoring NaN values.
+*
+* @param {PositiveInteger} W - window size
+* @throws {TypeError} must provide a positive integer
+* @returns {Function} accumulator function
+*
+* @example
+* var accumulator = incrnanmsumabs2( 3 );
+*
+* var sum = accumulator();
+* // returns null
+*
+* sum = accumulator( 2.0 );
+* // returns 4.0
+*
+* sum = accumulator( -5.0 );
+* // returns 29.0
+*
+* sum = accumulator( NaN );
+* // returns 29.0
+*
+* sum = accumulator( 3.0 );
+* // returns 38.0
+*
+* sum = accumulator();
+* // returns 38.0
+*/
+function incrnanmsumabs2( W ) {
+ var sum;
+ if ( !isPositiveInteger( W ) ) {
+ throw new TypeError( format( 'invalid argument. Must provide a positive integer. Value: `%s`.', W ) );
+ }
+ sum = 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
+ * @returns {(number|null)} sum or null
+ */
+ function accumulator( x ) {
+ if ( arguments.length === 0 ) {
+ return sum();
+ }
+ if ( isnan( x ) ) {
+ return sum();
+ }
+ return sum( x*x );
+ }
+}
+
+
+// EXPORTS //
+
+module.exports = incrnanmsumabs2;
diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/package.json b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/package.json
new file mode 100644
index 000000000000..4d30728df79b
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/package.json
@@ -0,0 +1,77 @@
+{
+ "name": "@stdlib/stats/incr/nanmsumabs2",
+ "version": "0.0.0",
+ "description": "Compute a moving sum of squared absolute values 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",
+ "incremental",
+ "accumulator",
+ "moving sum",
+ "sliding window",
+ "sliding",
+ "window",
+ "moving",
+ "rolling",
+ "absolute",
+ "value",
+ "abs",
+ "abs2",
+ "math.abs",
+ "magnitude",
+ "squared",
+ "nan"
+ ]
+}
diff --git a/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/test/test.js b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/test/test.js
new file mode 100644
index 000000000000..79460f2efb0e
--- /dev/null
+++ b/lib/node_modules/@stdlib/stats/incr/nanmsumabs2/test/test.js
@@ -0,0 +1,208 @@
+/**
+* @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 incrnanmsumabs2 = require( './../lib' );
+
+
+// TESTS //
+
+tape( 'main export is a function', function test( t ) {
+ t.ok( true, __filename );
+ t.strictEqual( typeof incrnanmsumabs2, '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() {
+ incrnanmsumabs2( value );
+ };
+ }
+});
+
+tape( 'the function returns an accumulator function', function test( t ) {
+ t.equal( typeof incrnanmsumabs2( 3 ), 'function', 'returns a function' );
+ t.end();
+});
+
+tape( 'the accumulator function computes a moving sum of squared absolute values incrementally', function test( t ) {
+ var expected;
+ var actual;
+ var data;
+ var acc;
+ var N;
+ var i;
+
+ data = [ 2.0, -3.0, 2.0, -4.0, 3.0, -4.0 ];
+ N = data.length;
+
+ acc = incrnanmsumabs2( 3 );
+
+ actual = [];
+ for ( i = 0; i < N; i++ ) {
+ actual.push( acc( data[ i ] ) );
+ }
+ expected = [ 4.0, 13.0, 17.0, 29.0, 29.0, 41.0 ];
+
+ t.deepEqual( actual, expected, 'returns expected incremental results' );
+ t.end();
+});
+
+tape( 'the accumulator function correctly handles NaN values by ignoring them', function test( t ) {
+ var expected;
+ var actual;
+ var data;
+ var acc;
+ var N;
+ var i;
+
+ data = [ 2.0, NaN, -3.0, NaN, 2.0, -4.0, 3.0, NaN, -4.0 ];
+ N = data.length;
+
+ acc = incrnanmsumabs2( 3 );
+
+ actual = [];
+ for ( i = 0; i < N; i++ ) {
+ actual.push( acc( data[ i ] ) );
+ }
+ expected = [ 4.0, 4.0, 13.0, 13.0, 17.0, 29.0, 29.0, 29.0, 41.0 ];
+
+ t.deepEqual( actual, expected, 'returns expected incremental results when handling NaN values' );
+ t.end();
+});
+
+tape( 'if not provided an input value, the accumulator function returns the current sum', function test( t ) {
+ var data;
+ var acc;
+ var i;
+
+ data = [ 2.0, -3.0, -5.0 ];
+ acc = incrnanmsumabs2( 2 );
+ for ( i = 0; i < data.length; i++ ) {
+ acc( data[ i ] );
+ }
+ t.equal( acc(), 34.0, 'returns expected value' );
+ t.end();
+});
+
+tape( 'if data has yet to be provided, the accumulator function returns `null`', function test( t ) {
+ var acc = incrnanmsumabs2( 3 );
+ t.equal( acc(), null, 'returns null' );
+ t.end();
+});
+
+tape( 'if only provided `NaN` values, the accumulator function returns `null`', function test( t ) {
+ var acc = incrnanmsumabs2( 3 );
+ acc( NaN );
+ acc( NaN );
+ acc( NaN );
+ t.equal( acc(), null, 'returns null' );
+ t.end();
+});
+
+tape( 'the accumulator function does not include `NaN` values in the window size count', function test( t ) {
+ var data;
+ var acc;
+ var i;
+
+ data = [ 2.0, -3.0, NaN, 5.0 ];
+ acc = incrnanmsumabs2( 3 );
+ for ( i = 0; i < data.length; i++ ) {
+ acc( data[ i ] );
+ }
+ t.equal( acc(), 38.0, 'returns expected value' );
+ t.end();
+});
+
+tape( 'the accumulator function can handle a mixture of `NaN` and non-`NaN` values', function test( t ) {
+ var expected;
+ var actual;
+ var data;
+ var acc;
+ var i;
+
+ data = [
+ NaN, // null (no values)
+ 3.14, // 9.8596
+ NaN, // still 9.8596
+ 3.14, // 19.7192
+ NaN, // still 19.7192
+ NaN, // still 19.7192
+ 3.14, // 29.5788
+ 3.14, // 29.5788 (3.14, 3.14, 3.14)
+ NaN, // 29.5788
+ 3.14 // 29.5788 (3.14, 3.14, 3.14)
+ ];
+
+ expected = [
+ null,
+ 9.8596,
+ 9.8596,
+ 19.7192,
+ 19.7192,
+ 19.7192,
+ 29.5788,
+ 29.5788,
+ 29.5788,
+ 29.5788
+ ];
+
+ acc = incrnanmsumabs2( 3 );
+
+ actual = [];
+ for ( i = 0; i < data.length; i++ ) {
+ actual.push( acc( data[ i ] ) );
+ }
+
+ for ( i = 0; i < expected.length; i++ ) {
+ if ( expected[i] === null ) {
+ t.equal( actual[i], null, 'returns expected value for index ' + i );
+ } else {
+ t.equal( actual[i], expected[i], 'returns expected value for index ' + i );
+ }
+ }
+
+ t.end();
+});