|
| 1 | +def minkowski_distance( |
| 2 | + point_a: list[float], |
| 3 | + point_b: list[float], |
| 4 | + order: int, |
| 5 | +) -> float: |
| 6 | + """ |
| 7 | + This function calculates the Minkowski distance for a given order between |
| 8 | + two n-dimensional points represented as lists. For the case of order = 1, |
| 9 | + the Minkowski distance degenerates to the Manhattan distance. For |
| 10 | + order = 2, the usual Euclidean distance is obtained. |
| 11 | +
|
| 12 | + https://en.wikipedia.org/wiki/Minkowski_distance |
| 13 | +
|
| 14 | + Note: due to floating point calculation errors the output of this |
| 15 | + function may be inaccurate. |
| 16 | +
|
| 17 | + >>> minkowski_distance([1.0, 1.0], [2.0, 2.0], 1) |
| 18 | + 2.0 |
| 19 | + >>> minkowski_distance([1.0, 2.0, 3.0, 4.0], [5.0, 6.0, 7.0, 8.0], 2) |
| 20 | + 8.0 |
| 21 | + >>> import numpy as np |
| 22 | + >>> np.isclose(5.0, minkowski_distance([5.0], [0.0], 3)) |
| 23 | + True |
| 24 | + >>> minkowski_distance([1.0], [2.0], -1) |
| 25 | + Traceback (most recent call last): |
| 26 | + ... |
| 27 | + ValueError: The order must be greater than or equal to 1. |
| 28 | + >>> minkowski_distance([1.0], [1.0, 2.0], 1) |
| 29 | + Traceback (most recent call last): |
| 30 | + ... |
| 31 | + ValueError: Both points must have the same dimension. |
| 32 | + """ |
| 33 | + if order < 1: |
| 34 | + raise ValueError("The order must be greater than or equal to 1.") |
| 35 | + |
| 36 | + if len(point_a) != len(point_b): |
| 37 | + raise ValueError("Both points must have the same dimension.") |
| 38 | + |
| 39 | + return sum(abs(a - b) ** order for a, b in zip(point_a, point_b)) ** (1 / order) |
| 40 | + |
| 41 | + |
| 42 | +if __name__ == "__main__": |
| 43 | + import doctest |
| 44 | + |
| 45 | + doctest.testmod() |
0 commit comments