time-to-botec/squiggle/node_modules/@stdlib/stats/base/snanminabs/lib/snanminabs.js

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/**
* @license Apache-2.0
*
* Copyright (c) 2020 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 isnanf = require( '@stdlib/math/base/assert/is-nanf' );
var abs = require( '@stdlib/math/base/special/abs' );
// MAIN //
/**
* Computes the minimum absolute value of a single-precision floating-point strided array, ignoring `NaN` values.
*
* @param {PositiveInteger} N - number of indexed elements
* @param {Float32Array} x - input array
* @param {integer} stride - stride length
* @returns {number} minimum absolute value
*
* @example
* var Float32Array = require( '@stdlib/array/float32' );
*
* var x = new Float32Array( [ 1.0, -2.0, NaN, 2.0 ] );
* var N = x.length;
*
* var v = snanminabs( N, x, 1 );
* // returns 1.0
*/
function snanminabs( N, x, stride ) {
var min;
var ix;
var v;
var i;
if ( N <= 0 ) {
return NaN;
}
if ( N === 1 || stride === 0 ) {
return abs( x[ 0 ] );
}
if ( stride < 0 ) {
ix = (1-N) * stride;
} else {
ix = 0;
}
for ( i = 0; i < N; i++ ) {
v = x[ ix ];
if ( v === v ) {
break;
}
ix += stride;
}
if ( i === N ) {
return NaN;
}
min = abs( v );
i += 1;
for ( i; i < N; i++ ) {
ix += stride;
v = abs( x[ ix ] );
if ( isnanf( v ) ) {
continue;
}
if ( v < min ) {
min = v;
}
}
return min;
}
// EXPORTS //
module.exports = snanminabs;