feat: add math/base/special/dirac-deltaf

PR-URL: stdlib-js#3363 Ref: stdlib-js#649 Co-authored-by: stdlib-bot <[email protected]> Reviewed-by: Philipp Burckhardt <[email protected]> --- type: pre_push_report description: Results of running various checks prior to pushing changes. report: - task: run_javascript_examples status: passed - task: run_c_examples status: passed - task: run_cpp_examples status: na - task: run_javascript_readme_examples status: passed - task: run_c_benchmarks status: passed - task: run_cpp_benchmarks status: na - task: run_fortran_benchmarks status: na - task: run_javascript_benchmarks status: passed - task: run_julia_benchmarks status: na - task: run_python_benchmarks status: na - task: run_r_benchmarks status: na - task: run_javascript_tests status: passed ---
saurabhraghuvanshii · Jan 9, 2025 · c369d83 · c369d83
1 parent 76642bf
commit c369d83
Show file tree

Hide file tree

Showing 28 changed files with 2,153 additions and 0 deletions.
diff --git a/lib/node_modules/@stdlib/math/base/special/dirac-deltaf/README.md b/lib/node_modules/@stdlib/math/base/special/dirac-deltaf/README.md
@@ -0,0 +1,221 @@
+<!--
+
+@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.
+
+-->
+
+# Dirac Delta
+
+> Evaluate the [Dirac delta function][dirac-delta-function] in single-precision floating-point format.
+
+<section class="intro">
+
+The [Dirac delta function][dirac-delta-function] may be loosely defined as
+
+<!-- <equation class="equation" label="eq:dirac_delta" align="center" raw="\delta = \begin{cases} \infty & \textrm{if}\ x = 0 \\ 0 & \textrm{if}\ x \neq 0\end{cases}" alt="Dirac delta function."> -->
+
+```math
+\delta = \begin{cases} \infty & \textrm{if}\ x = 0 \\ 0 & \textrm{if}\ x \neq 0\end{cases}
+```
+
+<!-- <div class="equation" align="center" data-raw-text="\delta = \begin{cases} \infty &amp; \textrm{if}\ x = 0 \\ 0 &amp; \textrm{if}\ x \neq 0\end{cases}" data-equation="eq:dirac_delta">
+    <img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@bb29798906e119fcb2af99e94b60407a270c9b32/lib/node_modules/@stdlib/math/base/special/dirac-delta/docs/img/equation_dirac_delta.svg" alt="Dirac delta function.">
+    <br>
+</div> -->
+
+<!-- </equation> -->
+
+and is constrained to satisfy the identity
+
+<!-- <equation class="equation" label="eq:dirac_delta_integral" align="center" raw="\int^{+\infty}_{-\infty} \delta(x)\ dx = 1" alt="Dirac delta function integral."> -->
+
+```math
+\int^{+\infty}_{-\infty} \delta(x)\ dx = 1
+```
+
+<!-- <div class="equation" align="center" data-raw-text="\int^{+\infty}_{-\infty} \delta(x)\ dx = 1" data-equation="eq:dirac_delta_integral">
+    <img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@bb29798906e119fcb2af99e94b60407a270c9b32/lib/node_modules/@stdlib/math/base/special/dirac-delta/docs/img/equation_dirac_delta_integral.svg" alt="Dirac delta function integral.">
+    <br>
+</div> -->
+
+<!-- </equation> -->
+
+Note that the [Dirac delta function][dirac-delta-function] is **not** a function in the traditional sense, as any real-valued function which is zero everywhere except at a single point, must have an integral equal to `0`.
+
+</section>
+
+<!-- /.intro -->
+
+<section class="usage">
+
+## Usage
+
+```javascript
+var diracDeltaf = require( '@stdlib/math/base/special/dirac-deltaf' );
+```
+
+#### diracDeltaf( x )
+
+Evaluates the [Dirac delta function][dirac-delta-function] in single-precision floating-point format.
+
+```javascript
+var v = diracDeltaf( 0.0 );
+// returns Infinity
+
+v = diracDeltaf( 3.14 );
+// returns 0.0
+
+v = diracDeltaf( NaN );
+// returns NaN
+```
+
+</section>
+
+<!-- /.usage -->
+
+<section class="examples">
+
+## Examples
+
+<!-- eslint no-undef: "error" -->
+
+```javascript
+var linspace = require( '@stdlib/array/base/linspace' );
+var diracDeltaf = require( '@stdlib/math/base/special/dirac-deltaf' );
+
+var x = linspace( -1.0, 1.0, 101 );
+
+var i;
+for ( i = 0; i < x.length; i++ ) {
+    console.log( 'dirac(%d) = %d', x[ i ], diracDeltaf( x[ i ] ) );
+}
+```
+
+</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/math/base/special/dirac_deltaf.h"
+```
+
+#### stdlib_base_dirac_deltaf( x )
+
+Evaluates the [Dirac delta function][dirac-delta-function] in single-precision floating-point format.
+
+```c
+float x = stdlib_base_dirac_deltaf( 0.0f );
+// returns Infinity
+
+x = stdlib_base_dirac_deltaf( 3.14f );
+// returns 0.0f
+```
+
+The function accepts the following arguments:
+
+-   **x**: `[in] float` input value.
+
+```c
+float stdlib_base_dirac_delta( const float x );
+```
+
+</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/math/base/special/dirac_deltaf.h"
+#include <stdlib.h>
+#include <stdio.h>
+
+int main( void ) {
+    const float x[] = { -1.0f, -0.5f, 0.0f, 0.5f, 1.0f, 3.14f, 2.0f };
+
+    float v;
+    int i;
+    for ( i = 0; i < 7; i++ ) {
+        v = stdlib_base_dirac_deltaf( x[ i ] );
+        printf( "dirac(%f) = %f\n", x[ i ], v );
+    }
+}
+```
+
+</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">
+
+[dirac-delta-function]: https://en.wikipedia.org/wiki/Dirac_delta_function
+
+<!-- <related-links> -->
+
+<!-- </related-links> -->
+
+</section>
+
+<!-- /.links -->
diff --git a/lib/node_modules/@stdlib/math/base/special/dirac-deltaf/benchmark/benchmark.js b/lib/node_modules/@stdlib/math/base/special/dirac-deltaf/benchmark/benchmark.js
@@ -0,0 +1,52 @@
+/**
+* @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/array/discrete-uniform' );
+var isnanf = require( '@stdlib/math/base/assert/is-nanf' );
+var pkg = require( './../package.json' ).name;
+var diracDeltaf = require( './../lib' );
+
+
+// MAIN //
+
+bench( pkg, function benchmark( b ) {
+	var x;
+	var y;
+	var i;
+
+	x = randu( 100, -50, 50 );
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		y = diracDeltaf( x[ i % x.length ] );
+		if ( isnanf( y ) ) {
+			b.fail( 'should not return NaN' );
+		}
+	}
+	b.toc();
+	if ( isnanf( y ) ) {
+		b.fail( 'should not return NaN' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});
diff --git a/lib/node_modules/@stdlib/math/base/special/dirac-deltaf/benchmark/benchmark.native.js b/lib/node_modules/@stdlib/math/base/special/dirac-deltaf/benchmark/benchmark.native.js
@@ -0,0 +1,61 @@
+/**
+* @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 resolve = require( 'path' ).resolve;
+var bench = require( '@stdlib/bench' );
+var randu = require( '@stdlib/random/array/discrete-uniform' );
+var isnanf = require( '@stdlib/math/base/assert/is-nanf' );
+var tryRequire = require( '@stdlib/utils/try-require' );
+var pkg = require( './../package.json' ).name;
+
+
+// VARIABLES //
+
+var diracDeltaf = tryRequire( resolve( __dirname, './../lib/native.js' ) );
+var opts = {
+	'skip': ( diracDeltaf instanceof Error )
+};
+
+
+// MAIN //
+
+bench( pkg+'::native', opts, function benchmark( b ) {
+	var x;
+	var y;
+	var i;
+
+	x = randu( 100, -50, 50 );
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		y = diracDeltaf( x[ i % x.length ] );
+		if ( isnanf( y ) ) {
+			b.fail( 'should not return NaN' );
+		}
+	}
+	b.toc();
+	if ( isnanf( y ) ) {
+		b.fail( 'should not return NaN' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});