gcd

Compute the greatest common divisor (gcd).

The greatest common divisor (gcd) of two non-zero integers a and b is the largest positive integer which divides both a and b without a remainder. The gcd is also known as the greatest common factor (gcf), highest common factor (hcf), highest common divisor, and greatest common measure (gcm).

Usage

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

gcd( a, b )

Computes the greatest common divisor (gcd).

var v = gcd( 48, 18 );
// returns 6

If both a and b are 0, the function returns 0.

var v = gcd( 0, 0 );
// returns 0

Both a and b must have integer values; otherwise, the function returns NaN.

var v = gcd( 3.14, 18 );
// returns NaN

v = gcd( 48, 3.14 );
// returns NaN

v = gcd( NaN, 18 );
// returns NaN

v = gcd( 48, NaN );
// returns NaN

Examples

var randu = require( '@stdlib/random/base/randu' );
var round = require( '@stdlib/math/base/special/round' );
var gcd = require( '@stdlib/math/base/special/gcd' );

var a;
var b;
var v;
var i;

for ( i = 0; i < 100; i++ ) {
    a = round( randu()*50.0 );
    b = round( randu()*50.0 );
    v = gcd( a, b );
    console.log( 'gcd(%d,%d) = %d', a, b, v );
}

References

Stein, Josef. 1967. "Computational problems associated with Racah algebra." Journal of Computational Physics 1 (3): 397–405. doi:10.1016/0021-9991(67)90047-2.