Set the Random Seed
Jaap MurreNeuroTask Scripting includes the excellent JavaScript random library seedrandom.js by David Bau (see https://github.com/davidbau/seedrandom). This example shows how to quickly create a seeded random number generator. See the Github page for more usage cases.
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var ran = new Math.seedrandom("Something"); // See https://github.com/davidbau/seedrandom
console.log(random()); // Built-in based on seedrandom is NOT seeded by this
console.log(ran()); // Ran is now a new pseudo-random generator, which is seeded
console.log(ran());