stdlib-js
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About stdlib...
</summary>
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exponent
[![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url]
Return an integer corresponding to the unbiased exponent of a [double-precision floating-point number][ieee754].
bash
npm install @stdlib/number-float64-base-exponent
javascript
var exponent = require( '@stdlib/number-float64-base-exponent' );
#### exponent( x )
Returns an integer corresponding to the unbiased exponent of a [double-precision floating-point number][ieee754].
javascript
var exp = exponent( 3.14e307 ); // => 2**1021 ~ 1e307
// returns 1021
exp = exponent( 3.14e-307 ); // => 2**-1019 ~ 1e-307
// returns -1019
exp = exponent( -3.14 );
// returns 1
exp = exponent( 0.0 );
// returns -1023
exp = exponent( NaN );
// returns 1024
javascript
var randu = require( '@stdlib/random-base-uniform' );
var discreteUniform = require( '@stdlib/random-base-discrete-uniform' );
var pow = require( '@stdlib/math-base-special-pow' );
var exponent = require( '@stdlib/number-float64-base-exponent' );
var frac;
var exp;
var x;
var e;
var i;
// Generate random numbers and extract their exponents...
for ( i = 0; i < 100; i++ ) {
frac = randu( 0.0, 10.0 );
exp = discreteUniform( -323, 323 );
x = frac * pow( 10.0, exp );
e = exponent( x );
console.log( 'x: %d. unbiased exponent: %d.', x, e );
}
c
#include "stdlib/number/float64/base/exponent.h"
#### stdlib_base_float64_exponent( x )
Returns an integer corresponding to the unbiased exponent of a [double-precision floating-point number][ieee754].
c
#include <stdint.h>
int32_t out = stdlib_base_float64_exponent( 3.14 );
The function accepts the following arguments:
- x: [in] double input value.
c
int32_t stdlib_base_float64_exponent( const double x );
c
#include "stdlib/number/float64/base/exponent.h"
#include <stdint.h>
#include <stdio.h>
#include <inttypes.h>
int main( void ) {
double x[] = { 4.0, 0.0, -0.0, 1.0, -1.0, 3.14, -3.14, 1.0e308, -1.0e308, 1.0/0.0, -1.0/0.0, 0.0/0.0 };
int32_t out;
int i;
for ( i = 0; i < 12; i++ ) {
out = stdlib_base_float64_exponent( x[ i ] );
printf( "%lf => out: %" PRId32 "\n", x[ i ], out );
}
}
@stdlib/number-float32/base/exponent][@stdlib/number/float32/base/exponent]: return an integer corresponding to the unbiased exponent of a single-precision floating-point number.
