minirank/minirank/metrics.py at master · cdegroc/minirank

Repository navigation

"""

most of this is copied from https://github.com/benhamner/Metrics

"""

import numpy as np

def levenshtein(s1, s2):

if len(s1) < len(s2):

return levenshtein(s2, s1)

if not len(s2):

return len(s1)

previous_row = range(len(s2) + 1)

for i, c1 in enumerate(s1):

current_row = [i+1]

for j, c2 in enumerate(s2):

insertions = previous_row[j+1] + 1

deletions = current_row[j] + 1

substitutions = previous_row[j] + (c1 != c2)

current_row.append(min(insertions, deletions, substitutions))

previous_row = current_row

return current_row[-1]