def test_cached_kernel_different_datasets(self):
skip_if_no_external('shogun', ver_dep='shogun:rev', min_version=4455)
# Inspired by the problem Swaroop ran into
k = LinearSGKernel(normalizer_cls=False)
k_ = LinearSGKernel(normalizer_cls=False) # to be cached
ck = CachedKernel(k_)
clf = sgSVM(svm_impl='libsvm', kernel=k, C=-1)
clf_ = sgSVM(svm_impl='libsvm', kernel=ck, C=-1)
cvte = CrossValidation(clf, NFoldPartitioner())
cvte_ = CrossValidation(clf_, NFoldPartitioner())
postproc=BinaryFxNode(mean_mismatch_error, 'targets')
te = ProxyMeasure(clf, postproc=postproc)
te_ = ProxyMeasure(clf_, postproc=postproc)
for r in xrange(2):
ds1 = datasets['uni2medium']
errs1 = cvte(ds1)
ck.compute(ds1)
ok_(ck._recomputed)
errs1_ = cvte_(ds1)
ok_(~ck._recomputed)
assert_array_equal(errs1, errs1_)
ds2 = datasets['uni3small']
errs2 = cvte(ds2)
ck.compute(ds2)
ok_(ck._recomputed)
errs2_ = cvte_(ds2)
ok_(~ck._recomputed)
assert_array_equal(errs2, errs2_)
ssel = np.round(datasets['uni2large'].samples[:5, 0]).astype(int)
te.train(datasets['uni3small'][::2])
terr = np.asscalar(te(datasets['uni3small'][ssel]))
te_.train(datasets['uni3small'][::2])
terr_ = np.asscalar(te_(datasets['uni3small'][ssel]))
ok_(~ck._recomputed)
ok_(terr == terr_)
def test_cache_speedup(self):
skip_if_no_external('shogun', ver_dep='shogun:rev', min_version=4455)
ck = sgSVM(kernel=CachedKernel(kernel=RbfSGKernel(sigma=2)), C=1)
sk = sgSVM(kernel=RbfSGKernel(sigma=2), C=1)
cv_c = CrossValidation(ck, NFoldPartitioner())
cv_s = CrossValidation(sk, NFoldPartitioner())
#data = datasets['uni4large']
P = 5000
data = normal_feature_dataset(snr=2, perlabel=200, nchunks=10,
means=np.random.randn(2, P), nfeatures=P)
t0 = time()
ck.params.kernel.compute(data)
cachetime = time()-t0
t0 = time()
cached_err = cv_c(data)
ccv_time = time()-t0
t0 = time()
norm_err = cv_s(data)
ncv_time = time()-t0
assert_almost_equal(np.asanyarray(cached_err),
np.asanyarray(norm_err))
ok_(cachetime<ncv_time)
ok_(ccv_time<ncv_time)
#print 'Regular CV time: %s seconds'%ncv_time
#print 'Caching time: %s seconds'%cachetime
#print 'Cached CV time: %s seconds'%ccv_time
speedup = ncv_time/(ccv_time+cachetime)
#print 'Speedup factor: %s'%speedup
# Speedup ideally should be 10, though it's not purely linear
self.failIf(speedup < 2, 'Problem caching data - too slow!')
def test_vstack_and_origids_issue(self):
# That is actually what swaroop hit
skip_if_no_external('shogun', ver_dep='shogun:rev', min_version=4455)
# Inspired by the problem Swaroop ran into
k = LinearSGKernel(normalizer_cls=False)
k_ = LinearSGKernel(normalizer_cls=False) # to be cached
ck = CachedKernel(k_)
clf = sgSVM(svm_impl='libsvm', kernel=k, C=-1)
clf_ = sgSVM(svm_impl='libsvm', kernel=ck, C=-1)
cvte = CrossValidation(clf, NFoldPartitioner())
cvte_ = CrossValidation(clf_, NFoldPartitioner())
ds = datasets['uni2large'].copy(deep=True)
ok_(~('orig_ids' in ds.sa)) # assure that there are None
ck.compute(ds) # so we initialize origids
ok_('origids' in ds.sa)
ds2 = ds.copy(deep=True)
ds2.samples = np.zeros(ds2.shape)
from mvpa2.base.dataset import vstack
ds_vstacked = vstack((ds2, ds))
# should complaint now since there would not be unique
# samples' origids
if __debug__:
assert_raises(ValueError, ck.compute, ds_vstacked)
ds_vstacked.init_origids('samples') # reset origids
ck.compute(ds_vstacked)
errs = cvte(ds_vstacked)
errs_ = cvte_(ds_vstacked)
# Following test would have failed since origids
# were just ints, and then non-unique after vstack
assert_array_equal(errs.samples, errs_.samples)