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floorsd

Round a numeric value to the nearest number toward negative infinity with N significant figures.

Installation

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

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

floorsd( x, n, b )

Rounds a numeric value to the nearest number toward negative infinity with n significant figures.

var v = floorsd( 3.141592653589793, 5, 10 );
// returns 3.1415

v = floorsd( 3.141592653589793, 1, 10 );
// returns 3.0

v = floorsd( 12368.0, 2, 10 );
// returns 12000.0

v = floorsd( 0.0313, 2, 2 );
// returns 0.03125

Examples

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

var x;
var y;
var i;

for ( i = 0; i < 100; i++ ) {
    x = (randu()*10000.0) - 5000.0;
    y = floorsd( x, 5, 10 );
    console.log( 'x: %d. Rounded: %d.', x, y );
}

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C APIs

Usage

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

stdlib_base_floorsd( x, n, b )

Rounds a numeric value to the nearest number toward negative infinity with n significant figures.

double out = stdlib_base_floorsd( 0.0313, 2, 2 );
// returns 0.03125

The function accepts the following arguments:

• x: [in] double input value.
• n: [in] int32_t number of significant figures.
• b: [in] int32_t base.

double stdlib_base_floorsd( const double x, const int32_t n, const int32_t b );

Examples

#include "stdlib/math/base/special/floorsd.h"
#include <stdio.h>
#include <stdint.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 };
    const int32_t n[] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
    const int32_t b[] = { 20, 19, 18, 17, 16, 15, 14, 13, 12, 11 };

    double v;
    int i;
    for ( i = 0; i < 10; i++ ) {
        v = stdlib_base_floorsd( x[ i ], n[ i ], b[ i ] );
        printf( "floorsd(%lf, %d, %d) = %lf\n", x[ i ], n[ i ], b[ i ], v );
    }
}

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See Also

• @stdlib/math-base/special/ceilsd: round a numeric value to the nearest number toward positive infinity with N significant figures.
• @stdlib/math-base/special/floor: round a double-precision floating-point number toward negative infinity.
• @stdlib/math-base/special/roundsd: round a numeric value to the nearest number with N significant figures.
• @stdlib/math-base/special/truncsd: round a numeric value to the nearest number toward zero with N significant figures.

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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.