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isOdd

Test if a finite double-precision floating-point number is an odd number.

Installation

npm install @stdlib/math-base-assert-is-odd

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

varisOdd=require('@stdlib/math-base-assert-is-odd');

isOdd( x )

Tests if a finite double-precision floating-point number is an odd number.

varbool=isOdd(5.0);// returns truebool=isOdd(-2.0);// returns falsebool=isOdd(0.0);// returns falsebool=isOdd(NaN);// returns false

Notes

• The function assumes a finitenumber. If provided positive or negative infinity, the function will return true, when, in fact, the result is undefined. If x can be infinite, wrap the implementation as follows:

  functioncheck(x){return(x<Infinity&&x>-Infinity&&isOdd(x));}varbool=check(Infinity);// returns falsebool=check(-Infinity);// returns false

Examples

vardiscreteUniform=require('@stdlib/random-array-discrete-uniform');varlogEachMap=require('@stdlib/console-log-each-map');varisOdd=require('@stdlib/math-base-assert-is-odd');varopts={'dtype': 'float64'};varx=discreteUniform(100,0,1000,opts);functionisOddWrapper(integer){return(isOdd(integer)) ? 'odd' : 'not odd';}logEachMap('%d is %s',x,isOddWrapper);

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C APIs

Usage

#include"stdlib/math/base/assert/is_odd.h"

stdlib_base_is_odd( x )

Tests if a finite double-precision floating-point number is an odd number.

#include<stdbool.h>boolout=stdlib_base_is_odd( 1.0 );
// returns trueout=stdlib_base_is_odd( 4.0 );
// returns false

The function accepts the following arguments:

• x: [in] double input value.

boolstdlib_base_is_odd( constdoublex );

Examples

#include"stdlib/math/base/assert/is_odd.h"#include<stdio.h>#include<stdbool.h>intmain( void ) {
constdoublex[] = { 5.0, -5.0, 3.14, -3.14, 0.0, 0.0/0.0 };
boolb;
inti;
for ( i=0; i<6; i++ ) {
b=stdlib_base_is_odd( x[ i ] );
printf( "Value: %lf. Is Odd? %s.\n", x[ i ], ( b ) ? "True" : "False" );
}
}

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See Also

• @stdlib/math-base/assert/is-even: test if a finite numeric value is an even number.

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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 © 2016-2026. The Stdlib Authors.