@technobuddha/library/variance/variance.cjs

A large library of useful functions

"use strict";
var __importDefault = (this && this.__importDefault) || function (mod) {
    return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.variance = void 0;
var mean_1 = __importDefault(require("lodash/mean"));
var sum_1 = __importDefault(require("lodash/sum"));
/**
 * Returns the unbiased sample variance of the arguments. For a definition,
 * see http://en.wikipedia.org/wiki/Variance
 *
 * @param datapoints Number samples to analyze.
 * @return The unbiased sample variance of the arguments (0 if fewer
 * than two samples were provided, or {@code NaN} if any of the samples is
 * not a valid number).
 */
function variance() {
    var datapoints = [];
    for (var _i = 0; _i < arguments.length; _i++) {
        datapoints[_i] = arguments[_i];
    }
    var sampleSize = datapoints.length;
    if (sampleSize < 2)
        return Number.NaN;
    var average = mean_1.default(datapoints);
    return sum_1.default(datapoints.map(function (val) { return Math.pow(val - average, 2); })) / (sampleSize - 1);
}
exports.variance = variance;
exports.default = variance;