forked from facebookresearch/faiss
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathtest_index.py
More file actions
528 lines (382 loc) · 14.2 KB
/
Copy pathtest_index.py
File metadata and controls
528 lines (382 loc) · 14.2 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
# Copyright (c) 2015-present, Facebook, Inc.
# All rights reserved.
#
# This source code is licensed under the BSD+Patents license found in the
# LICENSE file in the root directory of this source tree.
#! /usr/bin/env python2
"""this is a basic test script for simple indices work"""
import numpy as np
import unittest
import faiss
import tempfile
import os
import re
from common import get_dataset, get_dataset_2
class TestModuleInterface(unittest.TestCase):
def test_version_attribute(self):
assert hasattr(faiss, '__version__')
assert re.match('^\\d+\\.\\d+\\.\\d+$', faiss.__version__)
class EvalIVFPQAccuracy(unittest.TestCase):
def test_IndexIVFPQ(self):
d = 32
nb = 1000
nt = 1500
nq = 200
(xt, xb, xq) = get_dataset_2(d, nb, nt, nq)
d = xt.shape[1]
gt_index = faiss.IndexFlatL2(d)
gt_index.add(xb)
D, gt_nns = gt_index.search(xq, 1)
coarse_quantizer = faiss.IndexFlatL2(d)
index = faiss.IndexIVFPQ(coarse_quantizer, d, 32, 8, 8)
index.cp.min_points_per_centroid = 5 # quiet warning
index.train(xt)
index.add(xb)
index.nprobe = 4
D, nns = index.search(xq, 10)
n_ok = (nns == gt_nns).sum()
nq = xq.shape[0]
self.assertGreater(n_ok, nq * 0.66)
# check that and Index2Layer gives the same reconstruction
# this is a bit fragile: it assumes 2 runs of training give
# the exact same result.
index2 = faiss.Index2Layer(coarse_quantizer, 32, 8)
if True:
index2.train(xt)
else:
index2.pq = index.pq
index2.is_trained = True
index2.add(xb)
ref_recons = index.reconstruct_n(0, nb)
new_recons = index2.reconstruct_n(0, nb)
self.assertTrue(np.all(ref_recons == new_recons))
def test_IMI(self):
d = 32
nb = 1000
nt = 1500
nq = 200
(xt, xb, xq) = get_dataset_2(d, nb, nt, nq)
d = xt.shape[1]
gt_index = faiss.IndexFlatL2(d)
gt_index.add(xb)
D, gt_nns = gt_index.search(xq, 1)
nbits = 5
coarse_quantizer = faiss.MultiIndexQuantizer(d, 2, nbits)
index = faiss.IndexIVFPQ(coarse_quantizer, d, (1 << nbits) ** 2, 8, 8)
index.quantizer_trains_alone = 1
index.train(xt)
index.add(xb)
index.nprobe = 100
D, nns = index.search(xq, 10)
n_ok = (nns == gt_nns).sum()
# Should return 166 on mac, and 170 on linux.
self.assertGreater(n_ok, 165)
############# replace with explicit assignment indexes
nbits = 5
pq = coarse_quantizer.pq
centroids = faiss.vector_to_array(pq.centroids)
centroids = centroids.reshape(pq.M, pq.ksub, pq.dsub)
ai0 = faiss.IndexFlatL2(pq.dsub)
ai0.add(centroids[0])
ai1 = faiss.IndexFlatL2(pq.dsub)
ai1.add(centroids[1])
coarse_quantizer_2 = faiss.MultiIndexQuantizer2(d, nbits, ai0, ai1)
coarse_quantizer_2.pq = pq
coarse_quantizer_2.is_trained = True
index.quantizer = coarse_quantizer_2
index.reset()
index.add(xb)
D, nns = index.search(xq, 10)
n_ok = (nns == gt_nns).sum()
# should return the same result
self.assertGreater(n_ok, 165)
def test_IMI_2(self):
d = 32
nb = 1000
nt = 1500
nq = 200
(xt, xb, xq) = get_dataset_2(d, nb, nt, nq)
d = xt.shape[1]
gt_index = faiss.IndexFlatL2(d)
gt_index.add(xb)
D, gt_nns = gt_index.search(xq, 1)
############# redo including training
nbits = 5
ai0 = faiss.IndexFlatL2(int(d / 2))
ai1 = faiss.IndexFlatL2(int(d / 2))
coarse_quantizer = faiss.MultiIndexQuantizer2(d, nbits, ai0, ai1)
index = faiss.IndexIVFPQ(coarse_quantizer, d, (1 << nbits) ** 2, 8, 8)
index.quantizer_trains_alone = 1
index.train(xt)
index.add(xb)
index.nprobe = 100
D, nns = index.search(xq, 10)
n_ok = (nns == gt_nns).sum()
# should return the same result
self.assertGreater(n_ok, 165)
class TestMultiIndexQuantizer(unittest.TestCase):
def test_search_k1(self):
# verify codepath for k = 1 and k > 1
d = 64
nb = 0
nt = 1500
nq = 200
(xt, xb, xq) = get_dataset(d, nb, nt, nq)
miq = faiss.MultiIndexQuantizer(d, 2, 6)
miq.train(xt)
D1, I1 = miq.search(xq, 1)
D5, I5 = miq.search(xq, 5)
self.assertEqual(np.abs(I1[:, :1] - I5[:, :1]).max(), 0)
self.assertEqual(np.abs(D1[:, :1] - D5[:, :1]).max(), 0)
class TestScalarQuantizer(unittest.TestCase):
def test_4variants_ivf(self):
d = 32
nt = 2500
nq = 400
nb = 5000
(xt, xb, xq) = get_dataset_2(d, nb, nt, nq)
# common quantizer
quantizer = faiss.IndexFlatL2(d)
ncent = 64
index_gt = faiss.IndexFlatL2(d)
index_gt.add(xb)
D, I_ref = index_gt.search(xq, 10)
nok = {}
index = faiss.IndexIVFFlat(quantizer, d, ncent,
faiss.METRIC_L2)
index.cp.min_points_per_centroid = 5 # quiet warning
index.nprobe = 4
index.train(xt)
index.add(xb)
D, I = index.search(xq, 10)
nok['flat'] = (I[:, 0] == I_ref[:, 0]).sum()
for qname in "QT_4bit QT_4bit_uniform QT_8bit QT_8bit_uniform QT_fp16".split():
qtype = getattr(faiss.ScalarQuantizer, qname)
index = faiss.IndexIVFScalarQuantizer(quantizer, d, ncent,
qtype, faiss.METRIC_L2)
index.nprobe = 4
index.train(xt)
index.add(xb)
D, I = index.search(xq, 10)
nok[qname] = (I[:, 0] == I_ref[:, 0]).sum()
print(nok, nq)
self.assertGreaterEqual(nok['flat'], nq * 0.6)
# The tests below are a bit fragile, it happens that the
# ordering between uniform and non-uniform are reverted,
# probably because the dataset is small, which introduces
# jitter
self.assertGreaterEqual(nok['flat'], nok['QT_8bit'])
self.assertGreaterEqual(nok['QT_8bit'], nok['QT_4bit'])
self.assertGreaterEqual(nok['QT_8bit'], nok['QT_8bit_uniform'])
self.assertGreaterEqual(nok['QT_4bit'], nok['QT_4bit_uniform'])
self.assertGreaterEqual(nok['QT_fp16'], nok['QT_8bit'])
def test_4variants(self):
d = 32
nt = 2500
nq = 400
nb = 5000
(xt, xb, xq) = get_dataset(d, nb, nt, nq)
index_gt = faiss.IndexFlatL2(d)
index_gt.add(xb)
D_ref, I_ref = index_gt.search(xq, 10)
nok = {}
for qname in "QT_4bit QT_4bit_uniform QT_8bit QT_8bit_uniform QT_fp16".split():
qtype = getattr(faiss.ScalarQuantizer, qname)
index = faiss.IndexScalarQuantizer(d, qtype, faiss.METRIC_L2)
index.train(xt)
index.add(xb)
D, I = index.search(xq, 10)
nok[qname] = (I[:, 0] == I_ref[:, 0]).sum()
print(nok, nq)
self.assertGreaterEqual(nok['QT_8bit'], nq * 0.9)
self.assertGreaterEqual(nok['QT_8bit'], nok['QT_4bit'])
self.assertGreaterEqual(nok['QT_8bit'], nok['QT_8bit_uniform'])
self.assertGreaterEqual(nok['QT_4bit'], nok['QT_4bit_uniform'])
self.assertGreaterEqual(nok['QT_fp16'], nok['QT_8bit'])
class TestRangeSearch(unittest.TestCase):
def test_range_search(self):
d = 4
nt = 100
nq = 10
nb = 50
(xt, xb, xq) = get_dataset(d, nb, nt, nq)
index = faiss.IndexFlatL2(d)
index.add(xb)
Dref, Iref = index.search(xq, 5)
thresh = 0.1 # *squared* distance
lims, D, I = index.range_search(xq, thresh)
for i in range(nq):
Iline = I[lims[i]:lims[i + 1]]
Dline = D[lims[i]:lims[i + 1]]
for j, dis in zip(Iref[i], Dref[i]):
if dis < thresh:
li, = np.where(Iline == j)
self.assertTrue(li.size == 1)
idx = li[0]
self.assertGreaterEqual(1e-4, abs(Dline[idx] - dis))
class TestSearchAndReconstruct(unittest.TestCase):
def run_search_and_reconstruct(self, index, xb, xq, k=10, eps=None):
n, d = xb.shape
assert xq.shape[1] == d
assert index.d == d
D_ref, I_ref = index.search(xq, k)
R_ref = index.reconstruct_n(0, n)
D, I, R = index.search_and_reconstruct(xq, k)
self.assertTrue((D == D_ref).all())
self.assertTrue((I == I_ref).all())
self.assertEqual(R.shape[:2], I.shape)
self.assertEqual(R.shape[2], d)
# (n, k, ..) -> (n * k, ..)
I_flat = I.reshape(-1)
R_flat = R.reshape(-1, d)
# Filter out -1s when not enough results
R_flat = R_flat[I_flat >= 0]
I_flat = I_flat[I_flat >= 0]
recons_ref_err = np.mean(np.linalg.norm(R_flat - R_ref[I_flat]))
self.assertLessEqual(recons_ref_err, 1e-6)
def norm1(x):
return np.sqrt((x ** 2).sum(axis=1))
recons_err = np.mean(norm1(R_flat - xb[I_flat]))
print('Reconstruction error = %.3f' % recons_err)
if eps is not None:
self.assertLessEqual(recons_err, eps)
return D, I, R
def test_IndexFlat(self):
d = 32
nb = 1000
nt = 1500
nq = 200
(xt, xb, xq) = get_dataset(d, nb, nt, nq)
index = faiss.IndexFlatL2(d)
index.add(xb)
self.run_search_and_reconstruct(index, xb, xq, eps=0.0)
def test_IndexIVFFlat(self):
d = 32
nb = 1000
nt = 1500
nq = 200
(xt, xb, xq) = get_dataset(d, nb, nt, nq)
quantizer = faiss.IndexFlatL2(d)
index = faiss.IndexIVFFlat(quantizer, d, 32, faiss.METRIC_L2)
index.cp.min_points_per_centroid = 5 # quiet warning
index.nprobe = 4
index.train(xt)
index.add(xb)
self.run_search_and_reconstruct(index, xb, xq, eps=0.0)
def test_IndexIVFPQ(self):
d = 32
nb = 1000
nt = 1500
nq = 200
(xt, xb, xq) = get_dataset(d, nb, nt, nq)
quantizer = faiss.IndexFlatL2(d)
index = faiss.IndexIVFPQ(quantizer, d, 32, 8, 8)
index.cp.min_points_per_centroid = 5 # quiet warning
index.nprobe = 4
index.train(xt)
index.add(xb)
self.run_search_and_reconstruct(index, xb, xq, eps=1.0)
def test_MultiIndex(self):
d = 32
nb = 1000
nt = 1500
nq = 200
(xt, xb, xq) = get_dataset(d, nb, nt, nq)
index = faiss.index_factory(d, "IMI2x5,PQ8np")
faiss.ParameterSpace().set_index_parameter(index, "nprobe", 4)
index.train(xt)
index.add(xb)
self.run_search_and_reconstruct(index, xb, xq, eps=1.0)
def test_IndexTransform(self):
d = 32
nb = 1000
nt = 1500
nq = 200
(xt, xb, xq) = get_dataset(d, nb, nt, nq)
index = faiss.index_factory(d, "L2norm,PCA8,IVF32,PQ8np")
faiss.ParameterSpace().set_index_parameter(index, "nprobe", 4)
index.train(xt)
index.add(xb)
self.run_search_and_reconstruct(index, xb, xq)
class TestHNSW(unittest.TestCase):
def __init__(self, *args, **kwargs):
unittest.TestCase.__init__(self, *args, **kwargs)
d = 32
nt = 0
nb = 1500
nq = 500
(_, self.xb, self.xq) = get_dataset_2(d, nb, nt, nq)
index = faiss.IndexFlatL2(d)
index.add(self.xb)
Dref, Iref = index.search(self.xq, 1)
self.Iref = Iref
def test_hnsw(self):
d = self.xq.shape[1]
index = faiss.IndexHNSWFlat(d, 16)
index.add(self.xb)
Dhnsw, Ihnsw = index.search(self.xq, 1)
self.assertGreaterEqual((self.Iref == Ihnsw).sum(), 460)
self.io_and_retest(index, Dhnsw, Ihnsw)
def io_and_retest(self, index, Dhnsw, Ihnsw):
_, tmpfile = tempfile.mkstemp()
try:
faiss.write_index(index, tmpfile)
index2 = faiss.read_index(tmpfile)
finally:
if os.path.exists(tmpfile):
os.unlink(tmpfile)
Dhnsw2, Ihnsw2 = index2.search(self.xq, 1)
self.assertTrue(np.all(Dhnsw2 == Dhnsw))
self.assertTrue(np.all(Ihnsw2 == Ihnsw))
def test_hnsw_2level(self):
d = self.xq.shape[1]
quant = faiss.IndexFlatL2(d)
index = faiss.IndexHNSW2Level(quant, 256, 8, 8)
index.train(self.xb)
index.add(self.xb)
Dhnsw, Ihnsw = index.search(self.xq, 1)
self.assertGreaterEqual((self.Iref == Ihnsw).sum(), 310)
self.io_and_retest(index, Dhnsw, Ihnsw)
class TestIOError(unittest.TestCase):
def test_io_error(self):
d, n = 32, 1000
x = np.random.uniform(size=(n, d)).astype('float32')
index = faiss.IndexFlatL2(d)
index.add(x)
_, fname = tempfile.mkstemp()
try:
faiss.write_index(index, fname)
# should be fine
faiss.read_index(fname)
# now damage file
data = open(fname, 'rb').read()
data = data[:int(len(data) / 2)]
open(fname, 'wb').write(data)
# should make a nice readable exception that mentions the
try:
faiss.read_index(fname)
except RuntimeError as e:
if fname not in str(e):
raise
else:
raise
finally:
if os.path.exists(fname):
os.unlink(fname)
class TestDistancesPositive(unittest.TestCase):
def test_l2_pos(self):
"""
roundoff errors occur only with the L2 decomposition used
with BLAS, ie. in IndexFlatL2 and with
n > distance_compute_blas_threshold = 20
"""
d = 128
n = 100
rs = np.random.RandomState(1234)
x = rs.rand(n, d).astype('float32')
index = faiss.IndexFlatL2(d)
index.add(x)
D, I = index.search(x, 10)
assert np.all(D >= 0)
if __name__ == '__main__':
unittest.main()