Round a numeric value to the nearest integer.
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> Round a numeric value to the nearest integer.
``bash`
npm install @stdlib/math-base-special-round
`javascript`
var round = require( '@stdlib/math-base-special-round' );
#### round( x )
Rounds a numeric value to the nearest integer.
`javascript
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
`
- Ties are rounded toward positive infinity.
`javascript
var uniform = require( '@stdlib/random-array-uniform' );
var logEachMap = require( '@stdlib/console-log-each-map' );
var round = require( '@stdlib/math-base-special-round' );
var opts = {
'dtype': 'float64'
};
var x = uniform( 100, -50.0, 50.0, opts );
logEachMap( 'Value: %0.4f. Rounded: %0.4f.', x, round );
`
*
`c`
#include "stdlib/math/base/special/round.h"
#### stdlib_base_round( x )
Rounds a numeric value to the nearest integer.
`c`
double out = stdlib_base_round( -4.2 );
// returns -4.0
The function accepts the following arguments:
- x: [in] double input value.
`c`
double stdlib_base_round( const double x );
`c
#include "stdlib/math/base/special/round.h"
#include
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 );
}
}
`
*
- [@stdlib/math-base/special/ceil][@stdlib/math/base/special/ceil]: round a double-precision floating-point number toward positive infinity.
- [@stdlib/math-base/special/floor][@stdlib/math/base/special/floor]: round a double-precision floating-point number toward negative infinity.
- [@stdlib/math-base/special/roundn][@stdlib/math/base/special/roundn]: round a double-precision floating-point number to the nearest multiple of 10^n.
- [@stdlib/math-base/special/trunc][@stdlib/math/base/special/trunc]: round a double-precision floating-point number toward zero.
*
This package is part of [stdlib][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][stdlib], see the main project [repository][stdlib].
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---
See [LICENSE][stdlib-license].
Copyright © 2016-2026. The Stdlib [Authors][stdlib-authors].
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[umd]: https://github.com/umdjs/umd
[es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules
[deno-url]: https://github.com/stdlib-js/math-base-special-round/tree/deno
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[umd-url]: https://github.com/stdlib-js/math-base-special-round/tree/umd
[umd-readme]: https://github.com/stdlib-js/math-base-special-round/blob/umd/README.md
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[esm-readme]: https://github.com/stdlib-js/math-base-special-round/blob/esm/README.md
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[@stdlib/math/base/special/ceil]: https://www.npmjs.com/package/@stdlib/math-base-special-ceil
[@stdlib/math/base/special/floor]: https://www.npmjs.com/package/@stdlib/math-base-special-floor
[@stdlib/math/base/special/roundn]: https://www.npmjs.com/package/@stdlib/math-base-special-roundn
[@stdlib/math/base/special/trunc]: https://www.npmjs.com/package/@stdlib/math-base-special-trunc