Reduction

Definitions

1. The process of combining a collection of values into a single result by repeatedly applying a function. Also called fold or aggregate. Array.reduce() in JavaScript, functools.reduce() in Python, and Enum.reduce() in Elixir. MapReduce made it the backbone of big data processing.

   In plain English: Boiling a list of values down to one result by combining them step by step — like adding up a grocery receipt to get the total.

   Example: "[1, 2, 3, 4].reduce((sum, n) => sum + n, 0) returns 10 — the entire array reduced to a single number."

Related Terms

• Backtracking
• Big-O
• Binary Tree
• Chunk
• Discriminated Union
• Effect System
• Graph
• Hash Table
• Parse
• K-Means
• Pathfinding
• XML Parser