time-to-botec/js/node_modules/@stdlib/math/base/special/gamma1pm1/README.md

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@license Apache-2.0
Copyright (c) 2018 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.
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# gamma1pm1
> Compute `gamma(x+1) - 1`.
<section class="usage">
## Usage
```javascript
var gamma1pm1 = require( '@stdlib/math/base/special/gamma1pm1' );
```
#### gamma1pm1( x )
Computes `gamma(x+1) - 1` without cancellation errors for small `x` and where `gamma(x)` is the [gamma function][@stdlib/math/base/special/gamma].
```javascript
var v = gamma1pm1( 0.2 );
// returns ~-0.082
v = gamma1pm1( -8.5 );
// returns ~-1.0
v = gamma1pm1( 0.0 );
// returns 0.0
v = gamma1pm1( NaN );
// returns NaN
```
</section>
<!-- /.usage -->
<section class="examples">
## Examples
<!-- eslint no-undef: "error" -->
```javascript
var randu = require( '@stdlib/random/base/randu' );
var gamma1pm1 = require( '@stdlib/math/base/special/gamma1pm1' );
var x;
var i;
for ( i = 0; i < 100; i++ ) {
x = (randu()*10.0) - 5.0;
console.log( 'gamma(%d+1) - 1 = %d', x, gamma1pm1( x ) );
}
```
</section>
<!-- /.examples -->
<section class="links">
[@stdlib/math/base/special/gamma]: https://www.npmjs.com/package/@stdlib/math/tree/main/base/special/gamma
</section>
<!-- /.links -->