About stdlib...

We believe in a future in which the web is a preferred environment for numerical computation. To help realize this future, we've built stdlib. stdlib is a standard library, with an emphasis on numerical and scientific computation, written in JavaScript (and C) for execution in browsers and in Node.js.

The library is fully decomposable, being architected in such a way that you can swap out and mix and match APIs and functionality to cater to your exact preferences and use cases.

When you use stdlib, you can be absolutely certain that you are using the most thorough, rigorous, well-written, studied, documented, tested, measured, and high-quality code out there.

To join us in bringing numerical computing to the web, get started by checking us out on GitHub, and please consider financially supporting stdlib. We greatly appreciate your continued support!

trunc10

Round a numeric value to the nearest power of 10 toward zero.

Installation

npm install @stdlib/math-base-special-trunc10

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 trunc10 = require( '@stdlib/math-base-special-trunc10' );

trunc10( x )

Rounds a numeric value to the nearest power of 10 toward zero.

var v = trunc10( -4.2 );
// returns -1.0

v = trunc10( -4.5 );
// returns -1.0

v = trunc10( -4.6 );
// returns -1.0

v = trunc10( 9.99999 );
// returns 1.0

v = trunc10( 9.5 );
// returns 1.0

v = trunc10( 13.0 );
// returns 10.0

v = trunc10( -13.0 );
// returns -10.0

v = trunc10( 0.0 );
// returns 0.0

v = trunc10( -0.0 );
// returns -0.0

v = trunc10( Infinity );
// returns Infinity

v = trunc10( -Infinity );
// returns -Infinity

v = trunc10( NaN );
// returns NaN

Notes

• The function may not return accurate results for subnormals due to a general loss in precision.

  var v = trunc10( 1.0e-323 ); // should return 1.0e-323
  // returns 0.0

Examples

var randu = require( '@stdlib/random-base-randu' );
var trunc10 = require( '@stdlib/math-base-special-trunc10' );

var x;
var v;
var i;

for ( i = 0; i < 100; i++ ) {
    x = (randu()*100.0) - 50.0;
    v = trunc10( x );
    console.log( 'Value: %d. Rounded: %d.', x, v );
}

---

C APIs

Usage

#include "stdlib/math/base/special/trunc10.h"

stdlib_base_trunc10( x )

Rounds a numeric value to the nearest power of 10 toward zero.

double y = stdlib_base_trunc10( -4.2 );
// returns -1.0

The function accepts the following arguments:

• x: [in] double input value.

double stdlib_base_trunc10( const double x );

Examples

#include "stdlib/math/base/special/trunc10.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_trunc10( x[ i ] );
        printf( "trunc10(%lf) = %lf\n", x[ i ], y );
    }
}

---

See Also

• @stdlib/math-base/special/ceil10: round a numeric value to the nearest power of 10 toward positive infinity.
• @stdlib/math-base/special/floor10: round a numeric value to the nearest power of 10 toward negative infinity.
• @stdlib/math-base/special/round10: round a numeric value to the nearest power of 10 on a linear scale.
• @stdlib/math-base/special/trunc: round a double-precision floating-point number toward zero.
• @stdlib/math-base/special/trunc2: round a numeric value to the nearest power of two 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.