faiss/tests/test_index.py
Pankaj Singh 95e0a667ff Nightly failure fix - ignore searched vectors with identical distances (#3809)
Summary:
Pull Request resolved: https://github.com/facebookresearch/faiss/pull/3809

test_IndexIVFRQ is failing nightly GPU w/RAFT builds. These are false positive failures for the edge cases when the distance of a query vector to two candidate vectors is identical. In such cases, the search and search_and_reconstruct return these candidate vectors in a different order (on GPU w/Raft).

Current fix is to ignore the order of such ids with identical distances by sorting on distance and use id as tiebreaker. There is negligible performance implication (5ms extra), given the test candidate size is low.

Reviewed By: mengdilin, ramilbakhshyiev

Differential Revision: D61977915

fbshipit-source-id: 5f7a81c51c91a967013fb5e69e2bfee59be341c7
2024-08-29 11:00:05 -07:00

823 lines
23 KiB
Python

# Copyright (c) Facebook, Inc. and its affiliates.
#
# This source code is licensed under the MIT license found in the
# LICENSE file in the root directory of this source tree.
"""this is a basic test script for simple indices work"""
from __future__ import absolute_import, division, print_function
# no unicode_literals because it messes up in py2
import numpy as np
import unittest
import faiss
import tempfile
import os
import re
import warnings
from common_faiss_tests import get_dataset, get_dataset_2
from faiss.contrib.evaluation import check_ref_knn_with_draws
class TestModuleInterface(unittest.TestCase):
def test_version_attribute(self):
assert hasattr(faiss, '__version__')
assert re.match('^\\d+\\.\\d+\\.\\d+$', faiss.__version__)
class TestIndexFlat(unittest.TestCase):
def do_test(self, nq, metric_type=faiss.METRIC_L2, k=10):
d = 32
nb = 1000
nt = 0
(xt, xb, xq) = get_dataset_2(d, nt, nb, nq)
index = faiss.IndexFlat(d, metric_type)
### k-NN search
index.add(xb)
D1, I1 = index.search(xq, k)
if metric_type == faiss.METRIC_L2:
all_dis = ((xq.reshape(nq, 1, d) - xb.reshape(1, nb, d)) ** 2).sum(2)
Iref = all_dis.argsort(axis=1)[:, :k]
else:
all_dis = np.dot(xq, xb.T)
Iref = all_dis.argsort(axis=1)[:, ::-1][:, :k]
Dref = all_dis[np.arange(nq)[:, None], Iref]
# not too many elements are off.
self.assertLessEqual((Iref != I1).sum(), Iref.size * 0.0002)
# np.testing.assert_equal(Iref, I1)
np.testing.assert_almost_equal(Dref, D1, decimal=5)
### Range search
radius = float(np.median(Dref[:, -1]))
lims, D2, I2 = index.range_search(xq, radius)
for i in range(nq):
l0, l1 = lims[i:i + 2]
_, Il = D2[l0:l1], I2[l0:l1]
if metric_type == faiss.METRIC_L2:
Ilref, = np.where(all_dis[i] < radius)
else:
Ilref, = np.where(all_dis[i] > radius)
Il.sort()
Ilref.sort()
np.testing.assert_equal(Il, Ilref)
np.testing.assert_almost_equal(
all_dis[i, Ilref], D2[l0:l1],
decimal=5
)
def set_blas_blocks(self, small):
if small:
faiss.cvar.distance_compute_blas_query_bs = 16
faiss.cvar.distance_compute_blas_database_bs = 12
else:
faiss.cvar.distance_compute_blas_query_bs = 4096
faiss.cvar.distance_compute_blas_database_bs = 1024
def test_with_blas(self):
self.set_blas_blocks(small=True)
self.do_test(200)
self.set_blas_blocks(small=False)
def test_noblas(self):
self.do_test(10)
def test_with_blas_ip(self):
self.set_blas_blocks(small=True)
self.do_test(200, faiss.METRIC_INNER_PRODUCT)
self.set_blas_blocks(small=False)
def test_noblas_ip(self):
self.do_test(10, faiss.METRIC_INNER_PRODUCT)
def test_noblas_reservoir(self):
self.do_test(10, k=150)
def test_with_blas_reservoir(self):
self.do_test(200, k=150)
def test_noblas_reservoir_ip(self):
self.do_test(10, faiss.METRIC_INNER_PRODUCT, k=150)
def test_with_blas_reservoir_ip(self):
self.do_test(200, faiss.METRIC_INNER_PRODUCT, k=150)
class TestIndexFlatL2(unittest.TestCase):
def test_indexflat_l2_sync_norms_1(self):
d = 32
nb = 10000
nt = 0
nq = 16
k = 10
(xt, xb, xq) = get_dataset_2(d, nt, nb, nq)
# instantiate IndexHNSWFlat
index = faiss.IndexHNSWFlat(d, 32)
index.hnsw.efConstruction = 40
index.add(xb)
D1, I1 = index.search(xq, k)
index_l2 = faiss.downcast_index(index.storage)
index_l2.sync_l2norms()
D2, I2 = index.search(xq, k)
index_l2.clear_l2norms()
D3, I3 = index.search(xq, k)
# not too many elements are off.
self.assertLessEqual((I2 != I1).sum(), 1)
# np.testing.assert_equal(Iref, I1)
np.testing.assert_almost_equal(D2, D1, decimal=5)
# not too many elements are off.
self.assertLessEqual((I3 != I1).sum(), 0)
# np.testing.assert_equal(Iref, I1)
np.testing.assert_equal(D3, D1)
class EvalIVFPQAccuracy(unittest.TestCase):
def test_IndexIVFPQ(self):
d = 32
nb = 1000
nt = 1500
nq = 200
(xt, xb, xq) = get_dataset_2(d, nt, nb, nq)
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, nt, nb, 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, nt, nb, 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, nt, nb, 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 QT_bf16".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()
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'])
self.assertGreaterEqual(nok['QT_bf16'], 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 QT_bf16".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()
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'])
self.assertGreaterEqual(nok['QT_bf16'], nq * 0.9)
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)
np.testing.assert_almost_equal(D, D_ref, decimal=5)
check_ref_knn_with_draws(D_ref, I_ref, D, I)
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]))
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_IndexIVFRQ(self):
d = 32
nb = 1000
nt = 1500
nq = 200
(xt, xb, xq) = get_dataset(d, nb, nt, nq)
quantizer = faiss.IndexFlatL2(d)
index = faiss.IndexIVFResidualQuantizer(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 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)
class TestShardReplicas(unittest.TestCase):
def test_shard_flag_propagation(self):
d = 64 # dimension
nb = 1000
rs = np.random.RandomState(1234)
xb = rs.rand(nb, d).astype('float32')
nlist = 10
quantizer1 = faiss.IndexFlatL2(d)
quantizer2 = faiss.IndexFlatL2(d)
index1 = faiss.IndexIVFFlat(quantizer1, d, nlist)
index2 = faiss.IndexIVFFlat(quantizer2, d, nlist)
index = faiss.IndexShards(d, True)
index.add_shard(index1)
index.add_shard(index2)
self.assertFalse(index.is_trained)
index.train(xb)
self.assertTrue(index.is_trained)
self.assertEqual(index.ntotal, 0)
index.add(xb)
self.assertEqual(index.ntotal, nb)
index.remove_shard(index2)
self.assertEqual(index.ntotal, nb / 2)
index.remove_shard(index1)
self.assertEqual(index.ntotal, 0)
def test_replica_flag_propagation(self):
d = 64 # dimension
nb = 1000
rs = np.random.RandomState(1234)
xb = rs.rand(nb, d).astype('float32')
nlist = 10
quantizer1 = faiss.IndexFlatL2(d)
quantizer2 = faiss.IndexFlatL2(d)
index1 = faiss.IndexIVFFlat(quantizer1, d, nlist)
index2 = faiss.IndexIVFFlat(quantizer2, d, nlist)
index = faiss.IndexReplicas(d, True)
index.add_replica(index1)
index.add_replica(index2)
self.assertFalse(index.is_trained)
index.train(xb)
self.assertTrue(index.is_trained)
self.assertEqual(index.ntotal, 0)
index.add(xb)
self.assertEqual(index.ntotal, nb)
index.remove_replica(index2)
self.assertEqual(index.ntotal, nb)
index.remove_replica(index1)
self.assertEqual(index.ntotal, 0)
class TestReconsException(unittest.TestCase):
def test_recons_exception(self):
d = 64 # dimension
nb = 1000
rs = np.random.RandomState(1234)
xb = rs.rand(nb, d).astype('float32')
nlist = 10
quantizer = faiss.IndexFlatL2(d) # the other index
index = faiss.IndexIVFFlat(quantizer, d, nlist)
index.train(xb)
index.add(xb)
index.make_direct_map()
index.reconstruct(9)
self.assertRaises(
RuntimeError,
index.reconstruct, 100001
)
def test_reconstuct_after_add(self):
index = faiss.index_factory(10, 'IVF5,SQfp16')
index.train(faiss.randn((100, 10), 123))
index.add(faiss.randn((100, 10), 345))
index.make_direct_map()
index.add(faiss.randn((100, 10), 678))
# should not raise an exception
index.reconstruct(5)
index.reconstruct(150)
class TestReconsHash(unittest.TestCase):
def do_test(self, index_key):
d = 32
index = faiss.index_factory(d, index_key)
index.train(faiss.randn((100, d), 123))
# reference reconstruction
index.add(faiss.randn((100, d), 345))
index.add(faiss.randn((100, d), 678))
ref_recons = index.reconstruct_n(0, 200)
# with lookup
index.reset()
rs = np.random.RandomState(123)
ids = rs.choice(10000, size=200, replace=False).astype(np.int64)
index.add_with_ids(faiss.randn((100, d), 345), ids[:100])
index.set_direct_map_type(faiss.DirectMap.Hashtable)
index.add_with_ids(faiss.randn((100, d), 678), ids[100:])
# compare
for i in range(0, 200, 13):
recons = index.reconstruct(int(ids[i]))
self.assertTrue(np.all(recons == ref_recons[i]))
# test I/O
buf = faiss.serialize_index(index)
index2 = faiss.deserialize_index(buf)
# compare
for i in range(0, 200, 13):
recons = index2.reconstruct(int(ids[i]))
self.assertTrue(np.all(recons == ref_recons[i]))
# remove
toremove = np.ascontiguousarray(ids[0:200:3])
sel = faiss.IDSelectorArray(50, faiss.swig_ptr(toremove[:50]))
# test both ways of removing elements
nremove = index2.remove_ids(sel)
nremove += index2.remove_ids(toremove[50:])
self.assertEqual(nremove, len(toremove))
for i in range(0, 200, 13):
if i % 3 == 0:
self.assertRaises(
RuntimeError,
index2.reconstruct, int(ids[i])
)
else:
recons = index2.reconstruct(int(ids[i]))
self.assertTrue(np.all(recons == ref_recons[i]))
# index error should raise
self.assertRaises(
RuntimeError,
index.reconstruct, 20000
)
def test_IVFFlat(self):
self.do_test("IVF5,Flat")
def test_IVFSQ(self):
self.do_test("IVF5,SQfp16")
def test_IVFPQ(self):
self.do_test("IVF5,PQ4x4np")
class TestValidIndexParams(unittest.TestCase):
def test_IndexIVFPQ(self):
d = 32
nb = 1000
nt = 1500
nq = 200
(xt, xb, xq) = get_dataset_2(d, nt, nb, nq)
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)
# invalid nprobe
index.nprobe = 0
k = 10
self.assertRaises(RuntimeError, index.search, xq, k)
# invalid k
index.nprobe = 4
k = -10
self.assertRaises(AssertionError, index.search, xq, k)
# valid params
index.nprobe = 4
k = 10
D, nns = index.search(xq, k)
self.assertEqual(D.shape[0], nq)
self.assertEqual(D.shape[1], k)
def test_IndexFlat(self):
d = 32
nb = 1000
nt = 0
nq = 200
(xt, xb, xq) = get_dataset_2(d, nt, nb, nq)
index = faiss.IndexFlat(d, faiss.METRIC_L2)
index.add(xb)
# invalid k
k = -5
self.assertRaises(AssertionError, index.search, xq, k)
# valid k
k = 5
D, I = index.search(xq, k)
self.assertEqual(D.shape[0], nq)
self.assertEqual(D.shape[1], k)
class TestLargeRangeSearch(unittest.TestCase):
def test_range_search(self):
# test for https://github.com/facebookresearch/faiss/issues/1889
d = 256
nq = 16
nb = 1000000
# faiss.cvar.distance_compute_blas_threshold = 10
faiss.omp_set_num_threads(1)
index = faiss.IndexFlatL2(d)
xb = np.zeros((nb, d), dtype="float32")
index.add(xb)
xq = np.zeros((nq, d), dtype="float32")
lims, D, I = index.range_search(xq, 1.0)
assert len(D) == len(xb) * len(xq)
class TestRandomIndex(unittest.TestCase):
def test_random(self):
""" just check if several runs of search retrieve the
same results """
index = faiss.IndexRandom(32, 1000000000)
(xt, xb, xq) = get_dataset_2(32, 0, 0, 10)
Dref, Iref = index.search(xq, 10)
self.assertTrue(np.all(Dref[:, 1:] >= Dref[:, :-1]))
Dnew, Inew = index.search(xq, 10)
np.testing.assert_array_equal(Dref, Dnew)
np.testing.assert_array_equal(Iref, Inew)