def test_random_guesses(self):
data = g_mnemstudio_example_data
nclusters = 3
#XXX copypasted
# write an hdf file and create an associated data set
name_hdf = get_tmp_filename()
f_hdf = h5py.File(name_hdf)
dset = f_hdf.create_dataset('testset', data=data)
f_hdf.close()
f_hdf = h5py.File(name_hdf, 'r')
dset = f_hdf['testset']
#XXX copypasted
# write a tabular text file and re-open the file
name_stream = get_tmp_filename()
np.savetxt(name_stream, data)
f_stream = open(name_stream)
# check for errors in the simplest invocations
bigkmeans.kmeans(data, nclusters=nclusters)
bigkmeans.kmeans_hdf(dset, nclusters=nclusters)
bigkmeans.kmeans_ooc(f_stream, nclusters=nclusters)
#XXX copypasted
# close the hdf file and the tabular data file
f_hdf.close()
f_stream.close()
def test_cluster_loss_errors(self):
# this is a data and guess where a cluster is lost eventually
data = g_pathological_data
guess = g_pathological_guess
#XXX copypasted
# write an hdf file and create an associated data set
name_hdf = get_tmp_filename()
f_hdf = h5py.File(name_hdf)
dset = f_hdf.create_dataset('testset', data=data)
f_hdf.close()
f_hdf = h5py.File(name_hdf, 'r')
dset = f_hdf['testset']
#XXX copypasted
# write a tabular text file and re-open the file
name_stream = get_tmp_filename()
np.savetxt(name_stream, data)
f_stream = open(name_stream)
# The following three blocks should check errors.
# numpy
testing.assert_raises(
bigkmeans.ClusterLossError,
bigkmeans.kmeans,
data,
centroids=guess,
on_cluster_loss=bigkmeans.error_on_cluster_loss,
)
# hdf
testing.assert_raises(
bigkmeans.ClusterLossError,
bigkmeans.kmeans_hdf,
dset,
centroids=guess,
on_cluster_loss=bigkmeans.error_on_cluster_loss,
)
# out-of-core stream
testing.assert_raises(
bigkmeans.ClusterLossError,
bigkmeans.kmeans_ooc,
f_stream,
centroids=guess,
on_cluster_loss=bigkmeans.error_on_cluster_loss,
)
# Check that errors are not raised through these calls.
# Although a large number of restarts may occur...
benign_action_args = (
None,
bigkmeans.ignore_cluster_loss,
bigkmeans.return_on_cluster_loss,
bigkmeans.retry_after_cluster_loss,
)
for fn in benign_action_args:
bigkmeans.kmeans(data, centroids=guess, on_cluster_loss=fn)
bigkmeans.kmeans_hdf(dset, centroids=guess, on_cluster_loss=fn)
bigkmeans.kmeans_ooc(f_stream, centroids=guess, on_cluster_loss=fn)
# close the hdf file and the tabular data file
f_hdf.close()
f_stream.close()
def helper(
self, data,
maxiters=None, guess=None, nclusters=None,
on_cluster_loss=None,
):
# if no guess has been provided then we make a guess
if guess is None:
M, N = data.shape
indices = sorted(random.sample(xrange(M), nclusters))
guess = data[indices, :]
# write an hdf file and create an associated data set
name_hdf = get_tmp_filename()
f_hdf = h5py.File(name_hdf)
dset = f_hdf.create_dataset('testset', data=data)
f_hdf.close()
f_hdf = h5py.File(name_hdf, 'r')
dset = f_hdf['testset']
# write a tabular text file and re-open the file
name_stream = get_tmp_filename()
np.savetxt(name_stream, data)
f_stream = open(name_stream)
# check results for various vector quantization inner loops
for fn_block_update in (
bigkmeans.lloyd.update_block_pyvqcore,
bigkmeans.lloyd.update_block_scipy,
bigkmeans.lloyd.update_block_python,
):
# get the scipy kmeans results
vq_final_clust, vq_labels = scipy_cluster.vq.kmeans2(
data, guess, maxiters)
# get the bigkmeans numpy results
results = bigkmeans.kmeans(
data, centroids=guess, maxiters=maxiters,
on_cluster_loss=on_cluster_loss,
fn_block_update=fn_block_update,
)
np_init_clust, np_final_clust, np_labels = results
# get the bigkmeans hdf results
results = bigkmeans.kmeans_hdf(
dset, centroids=guess, maxiters=maxiters,
on_cluster_loss=on_cluster_loss,
fn_block_update=fn_block_update,
)
hdf_init_clust, hdf_final_clust, hdf_labels = results
# get the bigkmeans tabular text-based out-of-core results
results = bigkmeans.kmeans_ooc(
f_stream, centroids=guess, maxiters=maxiters,
on_cluster_loss=on_cluster_loss,
fn_block_update=fn_block_update,
)
ooc_init_clust, ooc_final_clust, ooc_labels = results
# check that the outputs are the same for all methods
for labels, final_clust in (
(np_labels, np_final_clust),
(hdf_labels, hdf_final_clust),
(ooc_labels, ooc_final_clust),
):
testing.assert_allclose(vq_final_clust, final_clust)
testing.assert_allclose(vq_labels, labels)
# close the hdf file and the tabular data file
f_hdf.close()
f_stream.close()
def main(args):
# Optionally read the initial centroids.
guess = None
if args.initial_centroids:
guess = np.loadtxt(args.initial_centroids, dtype=float, ndmin=2)
# Optionally specify an inner loop implementation choice.
fn_block_update = None
if args.inner_loop:
inner_loop_dict = {
'pyvqcore' : bigkmeans.lloyd.update_block_pyvqcore,
'scipy' : bigkmeans.lloyd.update_block_scipy,
'python' : bigkmeans.lloyd.update_block_python,
}
fn_block_update = inner_loop_dict[args.inner_loop]
# Open the data file and do the kmeans clustering.
# Note that we deliberately disallow using stdin
# because we require that the stream can be restarted
# so that we can do one pass through the open file per iteration.
if args.tabular_data_file:
with open(args.tabular_data_file) as data_stream:
guess, centroids, labels = bigkmeans.kmeans_ooc(
data_stream,
centroids=guess,
nclusters=args.nclusters,
on_cluster_loss=args.on_cluster_loss,
maxiters=args.maxiters,
maxrestarts=args.maxrestarts,
fn_block_update=fn_block_update,
verbose=args.verbose,
)
elif args.hdf_data_file:
if not h5py:
raise ImportError(
'sorry I cannot deal with hdf5 data files '
'unless the python package h5py is installed')
if not args.hdf_dataset_name:
raise Exception(
'If the data is in hdf format '
'then an hdf dataset name (--hdf-dataset-name) '
'must be specified '
'in addition to the name of the hdf file. '
'If you do not know the dataset name, '
'then you can try to use the program called hdfview '
'to search for your dataset within your hdf file.')
f = h5py.File(args.hdf_data_file, 'r')
dset = f[args.hdf_dataset_name]
guess, centroids, labels = bigkmeans.kmeans_hdf(
dset,
centroids=guess,
nclusters=args.nclusters,
on_cluster_loss=args.on_cluster_loss,
maxiters=args.maxiters,
maxrestarts=args.maxrestarts,
fn_block_update=fn_block_update,
verbose=args.verbose,
)
f.close()
# write the labels to stdout or to a user-specified file
if args.labels_out == '-':
np.savetxt(sys.stdout, labels, '%d')
elif args.labels_out:
np.savetxt(args.labels_out, labels, '%d')
# optionally write the centroids
if args.centroids_out == '-':
np.savetxt(sys.stdout, centroids)
elif args.centroids_out:
np.savetxt(args.centroids_out, centroids)
