API:RNG::next

From Spherical
Revision as of 15:45, 9 August 2017 by Bruce Pascoe (talk | contribs) (Reorganize page, add sub-headings for organization, add description)
Jump to: navigation, search


The RNG::next() method returns a random floating-point number in the range [0,1).

Usage

number = rng_object.next();

API Information

Description

RNG::next() generates a pseudorandom floating-point value greater than or equal to 0 but less than 1 and returns the value so generated. The value this function returns is entirely determined by the current state of the RNG instance before the call (see RNG::state). After calling this function, the state is advanced so a different value will be generated next time. If you save the state before RNG.next(), then restore it afterwards and call RNG.next() again, the same value will be generated.

Examples

Shuffle items in an array

let items = [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 ]
let rnGen = new RNG();
for (let i = items.length - 1; i > 0; --i) {
    let j = Math.floor(rnGen.next() * (i + 1));  // discrete [0,i]
    let orig_i = items[i];
    items[i] = items[j];
    items[j] = orig_i;
}