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About stdlib...

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sfloor

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Round each element in a single-precision floating-point strided array toward negative infinity.

Usage

import sfloor from 'https://cdn.jsdelivr.net/gh/stdlib-js/math-strided-special-sfloor@deno/mod.js';

sfloor( N, x, strideX, y, strideY )

Rounds each element in a single-precision floating-point strided array x toward negative infinity and assigns the results to elements in a single-precision floating-point strided array y.

import Float32Array from 'https://cdn.jsdelivr.net/gh/stdlib-js/array-float32@deno/mod.js';

var x = new Float32Array( [ -1.1, 1.1, 3.8, 4.5, 5.9 ] );

// Perform operation in-place:
sfloor( x.length, x, 1, x, 1 );
// x => <Float32Array>[ -2.0, 1.0, 3.0, 4.0, 5.0 ]

The function accepts the following arguments:

  • N: number of indexed elements.
  • x: input Float32Array.
  • strideX: index increment for x.
  • y: output Float32Array.
  • strideY: index increment for y.

The N and stride parameters determine which elements in x and y are accessed at runtime. For example, to index every other value in x and to index the first N elements of y in reverse order,

import Float32Array from 'https://cdn.jsdelivr.net/gh/stdlib-js/array-float32@deno/mod.js';

var x = new Float32Array( [ -1.1, 1.1, 3.8, 4.5, 5.9, -6.7 ] );
var y = new Float32Array( [ 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 ] );

sfloor( 3, x, 2, y, -1 );
// y => <Float32Array>[ 5.0, 3.0, -2.0, 0.0, 0.0, 0.0 ]

Note that indexing is relative to the first index. To introduce an offset, use typed array views.

import Float32Array from 'https://cdn.jsdelivr.net/gh/stdlib-js/array-float32@deno/mod.js';

// Initial arrays...
var x0 = new Float32Array( [ -1.1, 1.1, 3.8, 4.5, 5.9, -6.7 ] );
var y0 = new Float32Array( [ 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 ] );

// Create offset views...
var x1 = new Float32Array( x0.buffer, x0.BYTES_PER_ELEMENT*1 ); // start at 2nd element
var y1 = new Float32Array( y0.buffer, y0.BYTES_PER_ELEMENT*3 ); // start at 4th element

sfloor( 3, x1, -2, y1, 1 );
// y0 => <Float32Array>[ 0.0, 0.0, 0.0, -7.0, 4.0, 1.0 ]

sfloor.ndarray( N, x, strideX, offsetX, y, strideY, offsetY )

Rounds each element in a single-precision floating-point strided array x toward negative infinity and assigns the results to elements in a single-precision floating-point strided array y using alternative indexing semantics.

import Float32Array from 'https://cdn.jsdelivr.net/gh/stdlib-js/array-float32@deno/mod.js';

var x = new Float32Array( [ -1.1, 1.1, 3.8, 4.5, 5.9 ] );
var y = new Float32Array( [ 0.0, 0.0, 0.0, 0.0, 0.0 ] );

sfloor.ndarray( x.length, x, 1, 0, y, 1, 0 );
// y => <Float32Array>[ -2.0, 1.0, 3.0, 4.0, 5.0 ]

The function accepts the following additional arguments:

  • offsetX: starting index for x.
  • offsetY: starting index for y.

While typed array views mandate a view offset based on the underlying buffer, the offsetX and offsetY parameters support indexing semantics based on starting indices. For example, to index every other value in x starting from the second value and to index the last N elements in y,

import Float32Array from 'https://cdn.jsdelivr.net/gh/stdlib-js/array-float32@deno/mod.js';

var x = new Float32Array( [ -1.1, 1.1, 3.8, 4.5, 5.9, -6.7 ] );
var y = new Float32Array( [ 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 ] );

sfloor.ndarray( 3, x, 2, 1, y, -1, y.length-1 );
// y => <Float32Array>[ 0.0, 0.0, 0.0, -7.0, 4.0, 1.0 ]

Examples

import uniform from 'https://cdn.jsdelivr.net/gh/stdlib-js/random-base-uniform@deno/mod.js';
import Float32Array from 'https://cdn.jsdelivr.net/gh/stdlib-js/array-float32@deno/mod.js';
import sfloor from 'https://cdn.jsdelivr.net/gh/stdlib-js/math-strided-special-sfloor@deno/mod.js';

var x = new Float32Array( 10 );
var y = new Float32Array( 10 );

var i;
for ( i = 0; i < x.length; i++ ) {
    x[ i ] = uniform( -10.0, 10.0 );
}
console.log( x );
console.log( y );

sfloor.ndarray( x.length, x, 1, 0, y, -1, y.length-1 );
console.log( y );

See Also


Notice

This package is part of stdlib, a standard library with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.

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License

See LICENSE.

Copyright

Copyright © 2016-2024. The Stdlib Authors.