Compute the double word product of two unsigned 32-bit integers.
npm install @stdlib/math-base-special-uimuldwvar uimuldw = require( '@stdlib/math-base-special-uimuldw' );Multiplies two unsigned 32-bit integers and returns an array of two unsigned 32-bit integers (in big endian order) which represents the unsigned 64-bit integer product.
var v = uimuldw( 1, 10 );
// returns [ 0, 10 ]
v = uimuldw( 0x80000000, 0x80000000 ); // 2^31 * 2^31 = 4611686018427388000 => 32-bit integer overflow
// returns [ 1073741824, 0 ]- When computing the product of 32-bit integer values in double-precision floating-point format (the default JavaScript numeric data type), computing the double word product is necessary in order to avoid exceeding the maximum safe double-precision floating-point integer value.
var lpad = require( '@stdlib/string-left-pad' );
var uimuldw = require( '@stdlib/math-base-special-uimuldw' );
var i;
var j;
var y;
for ( i = 0xFFFFFFF0; i < 0xFFFFFFFF; i++ ) {
for ( j = i; j < 0xFFFFFFFF; j++) {
y = uimuldw( i, j );
console.log( '%d x %d = 0x%s%s', i, j, lpad( y[0].toString( 16 ), 8, '0' ), lpad( y[1].toString( 16 ), 8, '0' ) );
}
}@stdlib/math/base/special/imuldw: compute the double word product of two signed 32-bit integers.@stdlib/math/base/special/uimul: perform C-like multiplication of two unsigned 32-bit integers.
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