time-to-botec/squiggle/node_modules/@stdlib/math/base/special/kronecker-deltaf/README.md

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# Kronecker Delta
> Evaluate the [Kronecker delta][kronecker-delta] (single-precision).
<section class="intro">
The [Kronecker delta][kronecker-delta] is defined as
<!-- <equation class="equation" label="eq:kronecker_delta" align="center" raw="\delta_{ij} = \begin{cases} 1 & \textrm{if}\ i = j \\ 0 & \textrm{if}\ i \neq j\end{cases}" alt="Kronecker delta."> -->
<div class="equation" align="center" data-raw-text="\delta_{ij} = \begin{cases} 1 &amp; \textrm{if}\ i = j \\ 0 &amp; \textrm{if}\ i \neq j\end{cases}" data-equation="eq:kronecker_delta">
<img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@b245da8d5397f5cf6a71ec8a0147cf47d876eeb7/lib/node_modules/@stdlib/math/base/special/kronecker-deltaf/docs/img/equation_kronecker_delta.svg" alt="Kronecker delta.">
<br>
</div>
<!-- </equation> -->
</section>
<!-- /.intro -->
<section class="usage">
## Usage
```javascript
var kroneckerDeltaf = require( '@stdlib/math/base/special/kronecker-deltaf' );
```
#### kroneckerDeltaf( i, j )
Evaluates the [Kronecker delta][kronecker-delta] (single-precision).
```javascript
var v = kroneckerDeltaf( 3.14, 3.14 );
// returns 1.0
v = kroneckerDeltaf( 3.14, 0.0 );
// returns 0.0
v = kroneckerDeltaf( NaN, 3.14 );
// returns NaN
v = kroneckerDeltaf( 3.14, NaN );
// returns NaN
v = kroneckerDeltaf( NaN, NaN );
// returns NaN
```
</section>
<!-- /.usage -->
<section class="examples">
## Examples
<!-- eslint no-undef: "error" -->
```javascript
var linspace = require( '@stdlib/array/linspace' );
var kroneckerDeltaf = require( '@stdlib/math/base/special/kronecker-deltaf' );
var x = linspace( -1.0, 1.0, 101 );
var i;
for ( i = 0; i < x.length; i++ ) {
console.log( 'kronecker(%d,%d) = %d', x[ i ], 0.0, kroneckerDeltaf( x[ i ], 0.0 ) );
}
```
</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/kronecker_deltaf.h
```
#### stdlib_base_kronecker_deltaf( i, j )
Evaluates the Kronecker delta (single-precision).
```c
float v = stdlib_base_kronecker_deltaf( 3.0f, 3.0f );
// returns 1.0f
```
The function accepts the following arguments:
- **i**: `[in] float` input value.
- **j**: `[in] float` input value.
```c
float stdlib_base_kronecker_delta( const float i, const float j );
```
</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/kronecker_deltaf.h"
#include <stdio.h>
int main() {
float x[] = { 3.0f, 4.0f, 5.0f, 5.0f };
float y;
int i;
for ( i = 0; i < 4; i += 2 ) {
y = stdlib_base_kronecker_deltaf( x[ i ], x[ i+1 ] );
printf( "kronecker_delta(%f, %f) = %f\n", x[ i ], x[ i+1 ], y );
}
}
```
</section>
<!-- /.examples -->
</section>
<!-- /.c -->
<section class="links">
[kronecker-delta]: https://en.wikipedia.org/wiki/Kronecker_delta
</section>
<!-- /.links -->