feat: add lapack/base/disnan

lib/node_modules/@stdlib/lapack/base/disnan/README.md

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+<!--
+
+@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.
+
+-->
+
+# disnan
+
+> LAPACK auxiliary routine to test whether a double-precision floating-point number is `NaN`.
+
+<section class="usage">
+
+## Usage
+
+```javascript
+var disnan = require( '@stdlib/lapack/base/disnan' );
+```
+
+#### disnan( x )
+
+Tests whether a double-precision floating-point number is `NaN`.
+
+```javascript
+var bool = disnan( NaN );
+// returns true
+
+bool = disnan( 5.0 );
+// returns false
+```
+
+The function has the following parameters:
+
+-   **x**: input value.
+
+</section>
+
+<!-- /.usage -->
+
+<section class="notes">
+
+## Notes
+
+-   `disnan()` corresponds to the [LAPACK][lapack] auxiliary routine [`disnan`][lapack-disnan].
+
+</section>
+
+<!-- /.notes -->
+
+<section class="examples">
+
+## Examples
+
+<!-- eslint no-undef: "error" -->
+
+```javascript
+var discreteUniform = require( '@stdlib/random/array/discrete-uniform' );
+var logEachMap = require( '@stdlib/console/log-each-map' );
+var disnan = require( '@stdlib/lapack/base/disnan' );
+
+var opts = {
+    'dtype': 'float64'
+};
+var x = discreteUniform( 100, -50, 50, opts );
+
+logEachMap( 'disnan( %d ) = %s', x, disnan );
+```
+
+</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
+TODO
+```
+
+#### TODO
+
+TODO.
+
+```c
+TODO
+```
+
+TODO
+
+```c
+TODO
+```
+
+</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
+TODO
+```
+
+</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">
+
+[lapack]: https://www.netlib.org/lapack/explore-html/
+
+[lapack-disnan]: https://www.netlib.org/lapack/explore-html/d0/d4c/group__isnan_ga7aa3164d5df8d883754b0a70e9c7209c.html
+
+</section>
+
+<!-- /.links -->

lib/node_modules/@stdlib/lapack/base/disnan/benchmark/benchmark.js

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+/**
+* @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 isBoolean = require( '@stdlib/assert/is-boolean' ).isPrimitive;
+var pkg = require( './../package.json' ).name;
+var disnan = require( './../lib' );
+
+
+// MAIN //
+
+bench( pkg, function benchmark( b ) {
+	var len;
+	var x;
+	var z;
+	var i;
+
+	len = 100;
+	x = uniform( len, -50, 50 );
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		z = disnan( x[ i % len ] );
+		if ( typeof z !== 'boolean' ) {
+			b.fail( 'should return a boolean' );
+		}
+	}
+	b.toc();
+	if ( !isBoolean( z ) ) {
+		b.fail( 'should return a boolean' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});

lib/node_modules/@stdlib/lapack/base/disnan/docs/repl.txt

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+
+{{alias}}( x )
+    Tests whether a double-precision floating-point number is NaN.
+
+    Parameters
+    ----------
+    x: number
+        Input value.
+
+    Returns
+    -------
+    bool: boolean
+        Boolean indicating whether an input value is NaN.
+
+    Examples
+    --------
+    > var bool = {{alias}}( NaN )
+    true
+    > bool = {{alias}}( 5.0 )
+    false
+
+    See Also
+    --------
+

lib/node_modules/@stdlib/lapack/base/disnan/docs/types/index.d.ts

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+/*
+* @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
+
+/**
+* Tests whether a double-precision floating-point number is NaN.
+*
+* @param x - input value
+* @returns boolean indicating whether an input value is NaN
+*
+* @example
+* var bool = disnan( NaN );
+* // returns true
+*
+* @example
+* var bool = disnan( 5.0 );
+* // returns false
+*/
+declare function disnan( x: number ): boolean;
+
+
+// EXPORTS //
+
+export = disnan;

lib/node_modules/@stdlib/lapack/base/disnan/docs/types/test.ts

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+/*
+* @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 disnan = require( './index' );
+
+
+// TESTS //
+
+// The function returns a boolean...
+{
+	disnan( 8 ); // $ExpectType boolean
+}
+
+// The compiler throws an error if the function is provided a value other than a number...
+{
+	disnan( true ); // $ExpectError
+	disnan( false ); // $ExpectError
+	disnan( '5' ); // $ExpectError
+	disnan( [] ); // $ExpectError
+	disnan( {} ); // $ExpectError
+	disnan( ( x: number ): number => x ); // $ExpectError
+}
+
+// The compiler throws an error if the function is provided insufficient arguments...
+{
+	disnan(); // $ExpectError
+}

lib/node_modules/@stdlib/lapack/base/disnan/examples/index.js

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+/**
+* @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 discreteUniform = require( '@stdlib/random/array/discrete-uniform' );
+var logEachMap = require( '@stdlib/console/log-each-map' );
+var disnan = require( './../lib' );
+
+var opts = {
+	'dtype': 'float64'
+};
+var x = discreteUniform( 100, -50, 50, opts );
+
+logEachMap( 'disnan( %d ) = %s', x, disnan );