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isPrime

Test if a number is a prime.

A prime number is defined as an integer value greater than 1 which is only divisible by 1 and itself.

Installation

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

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 isPrime = require( '@stdlib/math-base-assert-is-prime' );

isPrime( x )

Tests if a number is a prime.

var bool = isPrime( 7.0 );
// returns true

Examples

var isPrime = require( '@stdlib/math-base-assert-is-prime' );

var bool = isPrime( 11.0 );
// returns true

bool = isPrime( 3.14 );
// returns false

bool = isPrime( NaN );
// returns false

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C APIs

Usage

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

stdlib_base_is_prime( x )

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

#include <stdbool.h>

bool out = stdlib_base_is_prime( 11.0 );
// returns true

out = stdlib_base_is_prime( 3.14 );
// returns false

The function accepts the following arguments:

• x: [in] double input value.

bool stdlib_base_is_prime( const double x );

Examples

#include "stdlib/math/base/assert/is_prime.h"
#include <stdio.h>
#include <stdbool.h>

int main( void ) {
    const double x[] = { 5.0, -5.0, 3.14, -3.14, -2.0, 2.0, 0.0, 0.0/0.0 };

    bool b;
    int i;
    for ( i = 0; i < 6; i++ ) {
        b = stdlib_base_is_prime( x[ i ] );
        printf( "Value: %lf. Is Prime? %s.\n", x[ i ], ( b ) ? "True" : "False" );
    }
}

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See Also

• @stdlib/math-base/assert/is-composite: test if a number is composite.
• @stdlib/math-base/assert/is-integer: test if a finite double-precision floating-point number is an 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.