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Math Functions

Mathematical operations and calculations. These utilities provide efficient mathematical operations for arrays and individual values.

Functions Overview

Function Description Parameters Returns
sum Sums array values array Sum number
sumBy Sums by iteratee array, iteratee Sum number
maxBy Gets max by iteratee array, iteratee Max element
minBy Gets min by iteratee array, iteratee Min element
add Adds two numbers augend, addend Sum number
divide Divides two numbers dividend, divisor Quotient number
mean Calculates mean array Mean number
meanBy Calculates mean by iteratee array, iteratee Mean number
multiply Multiplies two numbers multiplier, multiplicand Product number
subtract Subtracts two numbers minuend, subtrahend Difference number

Array Math Functions

sum(array)

Computes the sum of the values in array.

import { sum } from 'highdash';

console.log(sum([4, 2, 8, 6])); // 20
console.log(sum([1, 2, 3, 4, 5])); // 15
console.log(sum([])); // 0
console.log(sum([1, 2, NaN, 4])); // 7 (NaN treated as 0)

// Real-world examples
const prices = [19.99, 29.99, 39.99, 49.99];
console.log(sum(prices)); // 139.96

const scores = [85, 92, 78, 96, 88];
console.log(sum(scores)); // 439

sumBy(array, iteratee)

Computes the sum of the values in array using iteratee to transform each element.

import { sumBy } from 'highdash';

const objects = [{ 'n': 4 }, { 'n': 2 }, { 'n': 8 }, { 'n': 6 }];
console.log(sumBy(objects, o => o.n)); // 20
console.log(sumBy(objects, 'n')); // 20

// Real-world examples
const products = [
  { name: 'Laptop', price: 999, quantity: 2 },
  { name: 'Mouse', price: 25, quantity: 5 },
  { name: 'Keyboard', price: 75, quantity: 3 }
];

console.log(sumBy(products, 'price')); // 1099
console.log(sumBy(products, product => product.price * product.quantity)); // 2448

const employees = [
  { name: 'Alice', salary: 50000 },
  { name: 'Bob', salary: 60000 },
  { name: 'Charlie', salary: 55000 }
];

console.log(sumBy(employees, 'salary')); // 165000

maxBy(array, iteratee)

This method is like max except that it accepts iteratee which is invoked for each element in array to generate the criterion by which the value is ranked.

import { maxBy } from 'highdash';

const objects = [{ 'n': 1 }, { 'n': 2 }];
console.log(maxBy(objects, o => o.n)); // { 'n': 2 }
console.log(maxBy(objects, 'n')); // { 'n': 2 }

// Real-world examples
const products = [
  { name: 'Laptop', price: 999 },
  { name: 'Mouse', price: 25 },
  { name: 'Keyboard', price: 75 }
];

console.log(maxBy(products, 'price')); // { name: 'Laptop', price: 999 }
console.log(maxBy(products, product => product.price)); // { name: 'Laptop', price: 999 }

const students = [
  { name: 'Alice', score: 85 },
  { name: 'Bob', score: 92 },
  { name: 'Charlie', score: 78 }
];

console.log(maxBy(students, 'score')); // { name: 'Bob', score: 92 }

minBy(array, iteratee)

This method is like min except that it accepts iteratee which is invoked for each element in array to generate the criterion by which the value is ranked.

import { minBy } from 'highdash';

const objects = [{ 'n': 1 }, { 'n': 2 }];
console.log(minBy(objects, o => o.n)); // { 'n': 1 }
console.log(minBy(objects, 'n')); // { 'n': 1 }

// Real-world examples
const products = [
  { name: 'Laptop', price: 999 },
  { name: 'Mouse', price: 25 },
  { name: 'Keyboard', price: 75 }
];

console.log(minBy(products, 'price')); // { name: 'Mouse', price: 25 }

const students = [
  { name: 'Alice', score: 85 },
  { name: 'Bob', score: 92 },
  { name: 'Charlie', score: 78 }
];

console.log(minBy(students, 'score')); // { name: 'Charlie', score: 78 }

mean(array)

Computes the mean of the values in array.

import { mean } from 'highdash';

console.log(mean([4, 2, 8, 6])); // 5
console.log(mean([1, 2, 3, 4, 5])); // 3
console.log(mean([])); // NaN

// Real-world examples
const scores = [85, 92, 78, 96, 88];
console.log(mean(scores)); // 87.8

const temperatures = [72, 75, 78, 73, 76];
console.log(mean(temperatures)); // 74.8

meanBy(array, iteratee)

Computes the mean of the values in array using iteratee to transform each element.

import { meanBy } from 'highdash';

const objects = [{ 'n': 4 }, { 'n': 2 }, { 'n': 8 }, { 'n': 6 }];
console.log(meanBy(objects, o => o.n)); // 5
console.log(meanBy(objects, 'n')); // 5

// Real-world examples
const students = [
  { name: 'Alice', score: 85 },
  { name: 'Bob', score: 92 },
  { name: 'Charlie', score: 78 }
];

console.log(meanBy(students, 'score')); // 85

const products = [
  { name: 'Laptop', price: 999 },
  { name: 'Mouse', price: 25 },
  { name: 'Keyboard', price: 75 }
];

console.log(meanBy(products, 'price')); // 366.3333333333333

Basic Math Functions

add(augend, addend)

Adds two numbers.

import { add } from 'highdash';

console.log(add(6, 4)); // 10
console.log(add(1.5, 2.5)); // 4
console.log(add(-5, 3)); // -2

// Real-world examples
const total = add(19.99, 29.99); // 49.98
const age = add(25, 5); // 30

subtract(minuend, subtrahend)

Subtracts two numbers.

import { subtract } from 'highdash';

console.log(subtract(6, 4)); // 2
console.log(subtract(1.5, 2.5)); // -1
console.log(subtract(-5, 3)); // -8

// Real-world examples
const discount = subtract(100, 15); // 85
const remaining = subtract(100, 25); // 75

multiply(multiplier, multiplicand)

Multiplies two numbers.

import { multiply } from 'highdash';

console.log(multiply(6, 4)); // 24
console.log(multiply(1.5, 2.5)); // 3.75
console.log(multiply(-5, 3)); // -15

// Real-world examples
const total = multiply(19.99, 2); // 39.98
const area = multiply(10, 5); // 50

divide(dividend, divisor)

Divides two numbers.

import { divide } from 'highdash';

console.log(divide(6, 4)); // 1.5
console.log(divide(1.5, 2.5)); // 0.6
console.log(divide(-15, 3)); // -5

// Real-world examples
const average = divide(100, 4); // 25
const rate = divide(50, 2); // 25

Import Examples

// Import specific functions
import { sum, sumBy, maxBy, add } from 'highdash';

// Import from specific module (better tree-shaking)
import { sum } from 'highdash/math/sum.js';
import { sumBy } from 'highdash/math/sumBy.js';
import { maxBy } from 'highdash/math/maxBy.js';
import { add } from 'highdash/math/add.js';

// Import all math functions
import * as math from 'highdash/math';

Performance Notes

  • Array operations: Optimized for large arrays with efficient iteration
  • Type safety: Handles NaN values gracefully
  • Memory usage: Minimal memory overhead for calculations
  • Type safety: Full TypeScript support with proper type inference

Common Use Cases

  • Data analysis: Use sum, mean, maxBy, minBy for statistical analysis
  • Financial calculations: Use add, subtract, multiply, divide for precise calculations
  • Array processing: Use sumBy, meanBy for object array calculations
  • Performance metrics: Use maxBy, minBy for finding extremes
  • Aggregation: Use sum, sumBy for data aggregation
  • Averages: Use mean, meanBy for calculating averages