Generating Random Numbers in JS

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Generate random real numbers in $[0,1)$, i.e., $0\le\text{Math.random()} < 1$

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Math.random()
// Example return values:
// #1: 0.60958701902852
// #2: 0.16182155144292465
// #3: 0.30126821448898133

Randomly generate integers in $[0, n]$

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function randint1(n) { // Relatively balanced probability distribution
  return Math.round(Math.random() * n);
}

function randint2(n) { // n will never occur
  return Math.floor(Math.random() * n);
}

function randint3(n) { // Extremely low probability of 0, same as Math.random() producing 0
  return Math.ceil(Math.random() * n);
}

Generate random decimal numbers with one decimal place in $[0, n]$

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// May have floating-point precision errors, e.g., 0.30000000000000004, 0.7999999999999999
function randf(n) {
  return Math.round(Math.random() * n * 10) / 10;
}