Round

Round a numeric value to the nearest integer.

Installation

npm install @stdlib/math-base-special-round

Usage

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

round( x )

Rounds a numeric value to the nearest integer.

var v = round( -4.2 );
// returns -4.0

v = round( -4.5 );
// returns -4.0

v = round( -4.6 );
// returns -5.0

v = round( 9.99999 );
// returns 10.0

v = round( 9.5 );
// returns 10.0

v = round( 9.2 );
// returns 9.0

v = round( 0.0 );
// returns 0.0

v = round( -0.0 );
// returns -0.0

v = round( Infinity );
// returns Infinity

v = round( -Infinity );
// returns -Infinity

v = round( NaN );
// returns NaN

Notes

• Ties are rounded toward positive infinity.

Examples

var randu = require( '@stdlib/random-base-randu' );
var round = require( '@stdlib/math-base-special-round' );

var x;
var i;

for ( i = 0; i < 100; i++ ) {
    x = (randu()*100.0) - 50.0;
    console.log( 'Value: %d. Rounded: %d.', x, round( x ) );
}

C APIs

Usage

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

stdlib_base_round( x )

Rounds a numeric value to the nearest integer.

double out = stdlib_base_round( -4.2 );
// returns -4.0

The function accepts the following arguments:

• x: [in] double input value.

double stdlib_base_round( const double x );

Examples

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

int main( void ) {
    const double x[] = { -5.0, -3.89, -2.78, -1.67, -0.56, 0.56, 1.67, 2.78, 3.89, 5.0 };
    
    double v;
    int i;
    for ( i = 0; i < 10; i++ ) {
        v = stdlib_base_round( x[ i ] );
        printf( "round(%lf) = %lf\n", x[ i ], v );
    }
}

See Also

• @stdlib/math-base/special/ceil: round a double-precision floating-point number toward positive infinity.
• @stdlib/math-base/special/floor: round a double-precision floating-point number toward negative infinity.
• @stdlib/math-base/special/roundn: round a double-precision floating-point number to the nearest multiple of 10^n.
• @stdlib/math-base/special/trunc: round a double-precision floating-point number toward zero.

Notice

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.

Community

License

See LICENSE.

Copyright

Copyright © 2016-2024. The Stdlib Authors.