time-to-botec/squiggle/node_modules/@stdlib/stats/iter/mmin/README.md

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@license Apache-2.0
Copyright (c) 2019 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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# itermmin
> Create an [iterator][mdn-iterator-protocol] which iteratively computes a moving minimum value.
<section class="intro">
</section>
<!-- /.intro -->
<!-- Package usage documentation. -->
<section class="usage">
## Usage
```javascript
var itermmin = require( '@stdlib/stats/iter/mmin' );
```
#### itermmin( iterator, W )
Returns an [iterator][mdn-iterator-protocol] which iteratively computes a moving minimum value. The `W` parameter defines the number of iterated values over which to compute the moving minimum.
```javascript
var array2iterator = require( '@stdlib/array/to-iterator' );
var arr = array2iterator( [ 2.0, 1.0, 3.0, -7.0, -5.0 ] );
var it = itermmin( arr, 3 );
// Fill the window...
var m = it.next().value; // [2.0]
// returns 2.0
m = it.next().value; // [2.0, 1.0]
// returns 1.0
m = it.next().value; // [2.0, 1.0, 3.0]
// returns 1.0
// Window begins sliding...
m = it.next().value; // [1.0, 3.0, -7.0]
// returns -7.0
m = it.next().value; // [3.0, -7.0, -5.0]
// returns -7.0
```
</section>
<!-- /.usage -->
<!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
<section class="notes">
## Notes
- If an iterated value is non-numeric (including `NaN`), the function returns `NaN` for **at least** `W-1` future invocations. If non-numeric iterated values are possible, you are advised to provide an [`iterator`][mdn-iterator-protocol] which type checks and handles non-numeric values accordingly.
- 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 previously iterated values.
</section>
<!-- /.notes -->
<!-- Package usage examples. -->
<section class="examples">
## Examples
<!-- eslint no-undef: "error" -->
```javascript
var runif = require( '@stdlib/random/iter/uniform' );
var itermmin = require( '@stdlib/stats/iter/mmin' );
// Create an iterator for generating uniformly distributed pseudorandom numbers:
var rand = runif( -10.0, 10.0, {
'seed': 1234,
'iter': 100
});
// Create an iterator for iteratively computing a moving minimum value:
var it = itermmin( rand, 3 );
// Perform manual iteration...
var v;
while ( true ) {
v = it.next();
if ( typeof v.value === 'number' ) {
console.log( 'min: %d', v.value );
}
if ( v.done ) {
break;
}
}
```
</section>
<!-- /.examples -->
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<section class="references">
</section>
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<section class="links">
[mdn-iterator-protocol]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Iteration_protocols#The_iterator_protocol
</section>
<!-- /.links -->