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Truncate

Round a double-precision floating-point number toward zero.

Installation

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

Alternatively,

• To load the package in a website via a script tag without installation and bundlers, use the ES Module available on the esm branch (see README).
• If you are using Deno, visit the deno branch (see README for usage intructions).
• For use in Observable, or in browser/node environments, use the Universal Module Definition (UMD) build available on the umd branch (see README).

The branches.md file summarizes the available branches and displays a diagram illustrating their relationships.

To view installation and usage instructions specific to each branch build, be sure to explicitly navigate to the respective README files on each branch, as linked to above.

Usage

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

trunc( x )

Rounds a double-precision floating-point number toward zero.

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

v = trunc( 9.99999 );
// returns 9.0

v = trunc( 0.0 );
// returns 0.0

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

v = trunc( NaN );
// returns NaN

v = trunc( Infinity );
// returns Infinity

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

Examples

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

var x;
var i;

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

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C APIs

Usage

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

stdlib_base_trunc( x )

Rounds a double-precision floating-point number toward zero.

double y = stdlib_base_trunc( 3.14 );
// returns 3.0

The function accepts the following arguments:

• x: [in] double input value.

double stdlib_base_trunc( const double x );

Examples

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

int main( void ) {
    const double x[] = { 3.14, -3.14, 0.0, 0.0/0.0 };

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

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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/round: round a numeric value to the nearest integer.

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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

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License

See LICENSE.

Copyright

Copyright © 2016-2024. The Stdlib Authors.