About stdlib...
We believe in a future in which the web is a preferred environment for numerical computation. To help realize this future, we've built stdlib. stdlib is a standard library, with an emphasis on numerical and scientific computation, written in JavaScript (and C) for execution in browsers and in Node.js.
The library is fully decomposable, being architected in such a way that you can swap out and mix and match APIs and functionality to cater to your exact preferences and use cases.
When you use stdlib, you can be absolutely certain that you are using the most thorough, rigorous, well-written, studied, documented, tested, measured, and high-quality code out there.
To join us in bringing numerical computing to the web, get started by checking us out on GitHub, and please consider financially supporting stdlib. We greatly appreciate your continued support!
Return a normal number
y
and exponentexp
satisfyingx = y * 2^exp
.
npm install @stdlib/number-float32-base-normalize
var normalizef = require( '@stdlib/number-float32-base-normalize' );
Returns a normal number y
and exponent exp
satisfying x = y * 2^exp
.
var toFloat32 = require( '@stdlib/number-float64-base-to-float32' );
var out = normalizef( toFloat32( 1.401e-45 ) );
// returns [ 1.1754943508222875e-38, -23 ]
By default, the function returns y
and exp
as a two-element array
.
var toFloat32 = require( '@stdlib/number-float64-base-to-float32' );
var pow = require( '@stdlib/math-base-special-pow' );
var out = normalizef( toFloat32( 1.401e-45 ) );
// returns [ 1.1754943508222875e-38, -23 ]
var y = out[ 0 ];
var exp = out[ 1 ];
var bool = ( y*pow(2, exp) === toFloat32(1.401e-45) );
// returns true
The function expects a finite, non-zero single-precision floating-point number x
. If x == 0
,
var out = normalizef( 0.0 );
// returns [ 0.0, 0 ];
If x
is either positive or negative infinity
or NaN
,
var PINF = require( '@stdlib/constants-float32-pinf' );
var NINF = require( '@stdlib/constants-float32-ninf' );
var out = normalizef( PINF );
// returns [ Infinity, 0 ]
out = normalizef( NINF );
// returns [ -Infinity, 0 ]
out = normalizef( NaN );
// returns [ NaN, 0 ]
Returns a normal number y
and exponent exp
satisfying x = y * 2^exp
and assigns results to a provided output array.
var toFloat32 = require( '@stdlib/number-float64-base-to-float32' );
var Float32Array = require( '@stdlib/array-float32' );
var out = new Float32Array( 2 );
var v = normalizef.assign( toFloat32( 1.401e-45 ), out, 1, 0 );
// returns <Float32Array>[ 1.1754943508222875e-38, -23 ]
var bool = ( v === out );
// returns true
- While the function accepts higher precision floating-point numbers, beware that providing such numbers can be a source of subtle bugs as the relation
x = y * 2^exp
may not hold.
var randu = require( '@stdlib/random-base-randu' );
var round = require( '@stdlib/math-base-special-round' );
var pow = require( '@stdlib/math-base-special-pow' );
var toFloat32 = require( '@stdlib/number-float64-base-to-float32' );
var normalizef = require( '@stdlib/number-float32-base-normalize' );
var frac;
var exp;
var x;
var v;
var i;
// Generate denormalized single-precision floating-point numbers and then normalize them...
for ( i = 0; i < 100; i++ ) {
frac = randu() * 10.0;
exp = 38 + round( randu()*6.0 );
x = frac * pow( 10.0, -exp );
x = toFloat32( x );
v = normalizef( x );
console.log( '%d = %d * 2^%d = %d', x, v[0], v[1], v[0]*pow(2.0, v[1]) );
}
#include "stdlib/number/float32/base/normalize.h"
Returns a normal number y
and exponent exp
satisfying x = y * 2^exp
.
#include <stdint.h>
float y;
int32_t exp;
stdlib_base_float32_normalize( 3.14, &y, &exp );
The function accepts the following arguments:
-
x:
[in] float
input value. -
y:
[out] float*
destination for normal number. -
exp:
[out] int32_t*
destination for exponent.
void stdlib_base_float32_normalize( const float x, float *y, int32_t *exp );
#include "stdlib/number/float32/base/normalize.h"
#include <stdint.h>
#include <stdio.h>
int main( void ) {
float x[] = { 4.0f, 0.0f, -0.0f, 1.0f, -1.0f, 3.14f, -3.14f, 1.0e-38f, -1.0e-38f, 1.0f/0.0f, -1.0f/0.0f, 0.0f/0.0f };
int32_t exp;
float y;
int i;
for ( i = 0; i < 12; i++ ) {
stdlib_base_float32_normalize( x[ i ], &y, &exp );
printf( "%f => y: %f, exp: %" PRId32 "\n", x[ i ], y, exp );
}
}
-
@stdlib/number-float64/base/normalize
: return a normal numbery
and exponentexp
satisfyingx = y * 2^exp
.
This package is part of stdlib, a standard library for JavaScript and Node.js, 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.
See LICENSE.
Copyright © 2016-2024. The Stdlib Authors.