refactor(es modules): modulize utils

src/utils/probabilityUtils.ts

@@ -0,0 +1,84 @@
+import {ERROR} from "@/config/logging";
+import {minmax, rn} from "./numberUtils";
+
+const d3 = window.d3;
+
+// random number in range
+export function rand(min: number, max: number) {
+  if (min === undefined && max === undefined) return Math.random();
+  if (max === undefined) {
+    max = min;
+    min = 0;
+  }
+  return Math.floor(Math.random() * (max - min + 1)) + min;
+}
+
+// probability shorthand
+export function P(probability: number) {
+  if (probability >= 1) return true;
+  if (probability <= 0) return false;
+  return Math.random() < probability;
+}
+
+export function each(n: number) {
+  return (i: number) => i % n === 0;
+}
+
+// random number using normal distribution
+export function gauss(expected = 100, deviation = 30, min = 0, max = 300, round = 0) {
+  const randomValue = d3.randomNormal(expected, deviation);
+  const clamped = minmax(randomValue(), min, max);
+  return rn(clamped, round);
+}
+
+// probability shorthand for floats
+export function Pint(float: number) {
+  return ~~float + +P(float % 1);
+}
+
+// return random value from the array
+export function ra<T>(array: T[]) {
+  return array[Math.floor(Math.random() * array.length)];
+}
+
+// return random value from weighted array
+export function rw(object: {[key: string]: number}) {
+  const weightedArray = Object.entries(object)
+    .map(([choise, weight]) => new Array(weight).fill(choise))
+    .flat();
+  return ra(weightedArray);
+}
+
+// return a random integer from min to max biased towards one end based on exponent distribution (the bigger ex the higher bias towards min)
+export function biased(min: number, max: number, ex: number) {
+  return Math.round(min + (max - min) * Math.pow(Math.random(), ex));
+}
+
+// get number from string in format "1-3" or "2" or "0.5"
+export function getNumberInRange(rangeString: string) {
+  if (typeof rangeString !== "string") {
+    ERROR && console.error("The value should be a string", rangeString);
+    return 0;
+  }
+
+  const rangeNumber = Number(rangeString);
+  if (!isNaN(rangeNumber)) return Pint(rangeNumber);
+
+  const negative = rangeString.startsWith("-");
+  const sign = negative ? -1 : 1;
+  if (negative) rangeString = rangeString.substring(1);
+
+  const [min, max] = rangeString.split("-");
+  const count = rand(sign * +min, +max);
+
+  if (isNaN(count) || count < 0) {
+    ERROR && console.error("Cannot parse number. Check the format", rangeString);
+    return 0;
+  }
+
+  return count;
+}
+
+export function generateSeed() {
+  return String(Math.floor(Math.random() * 1e9));
+}