distance function

A distance function is a mathematical way to measure how different or far apart two things are from each other. Think of it as a way to calculate the space or difference between two points, objects, or data items. For example, in everyday terms, measuring the straight-line distance between two cities on a map uses a distance function. In data analysis and machine learning, it helps compare items based on their features, enabling algorithms to group similar items or identify outliers, ultimately helping us understand relationships between data points efficiently.