annoy_vector_index_build_save_and_nearest_neighbor_search.py

1from annoy import AnnoyIndex
2import random
3
4f = 40  # Length of item vector that will be indexed
5t = AnnoyIndex(f, 'angular')
6for i in range(1000):
7    v = [random.gauss(0, 1) for z in range(f)]
8    t.add_item(i, v)
9
10t.build(10) # 10 trees
11t.save('test.ann')
12
13# ...
14
15u = AnnoyIndex(f, 'angular')
16u.load('test.ann') # super fast, will just mmap the file
17print(u.get_nns_by_item(0, 1000)) # will find the 1000 nearest neighbors