inv

Compute the multiplicative inverse of a double-precision floating-point number.

The multiplicative inverse (or reciprocal) is defined as

$$y = \frac{1}{x}$$

Usage

var inv = require( '@stdlib/math/base/special/inv' );

inv( x )

Computes the multiplicative inverse of a double-precision floating-point number x.

var v = inv( -1.0 );
// returns -1.0

v = inv( 2.0 );
// returns 0.5

v = inv( 0.0 );
// returns Infinity

v = inv( -0.0 );
// returns -Infinity

v = inv( NaN );
// returns NaN

Examples

var discreteUniform = require( '@stdlib/random/array/discrete-uniform' );
var logEachMap = require( '@stdlib/console/log-each-map' );
var inv = require( '@stdlib/math/base/special/inv' );

var opts = {
    'dtype': 'float64'
};
var x = discreteUniform( 100, -50, 50, opts );

logEachMap( 'inv(%0.4f) = %0.4f', x, inv );

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C APIs

Usage

#include "stdlib/math/base/special/inv.h"

stdlib_base_inv( x )

Computes the multiplicative inverse of a double-precision floating-point number.

double y = stdlib_base_inv( 2.0 );
// returns 0.5

The function accepts the following arguments:

• x: [in] double input value.

double stdlib_base_inv( const double x );

Examples

#include "stdlib/math/base/special/inv.h"
#include <stdio.h>

int main( void ) {
    const double x[] = { 3.0, 4.0, 5.0, 12.0 };

    double y;
    int i;
    for ( i = 0; i < 4; i++ ) {
        y = stdlib_base_inv( x[ i ] );
        printf( "inv(%lf) = %lf\n", x[ i ], y );
    }
}

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See Also

• @stdlib/math/base/special/pow: exponential function.