3.6 KiB
3.6 KiB
itermmin
Create an iterator which iteratively computes a moving minimum value.
Usage
var itermmin = require( '@stdlib/stats/iter/mmin' );
itermmin( iterator, W )
Returns an iterator which iteratively computes a moving minimum value. The W
parameter defines the number of iterated values over which to compute the moving minimum.
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
Notes
- If an iterated value is non-numeric (including
NaN
), the function returnsNaN
for at leastW-1
future invocations. If non-numeric iterated values are possible, you are advised to provide aniterator
which type checks and handles non-numeric values accordingly. - As
W
values are needed to fill the window buffer, the firstW-1
returned values are calculated from smaller sample sizes. Until the window is full, each returned value is calculated from all previously iterated values.
Examples
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;
}
}