def fit_protein_pca(yaml_file):
mdl_dir = yaml_file["mdl_dir"]
mdl_params = yaml_file["mdl_params"]
current_mdl_params={}
for i in mdl_params.keys():
if i.startswith("pca__"):
current_mdl_params[i.split("pca__")[1]] = mdl_params[i]
protein_pca_mdl = PCA(**current_mdl_params)
for protein in yaml_file["protein_list"]:
print("Fitting to protein %s" % protein)
with enter_protein_data_dir(yaml_file, protein):
featurized_traj = sorted(glob.glob("./%s/*.jl" %
yaml_file["feature_dir"]), key=keynat)
for f in featurized_traj:
featurized_path = verboseload(f)
try:
protein_pca_mdl.partial_fit(featurized_path)
except:
pass
print("Done partial fitting to protein %s" % protein)
# dumping the pca_mdl
pca_mdl_path = os.path.join(mdl_dir, "pca_mdl.pkl")
verbosedump(protein_pca_mdl, pca_mdl_path)
return
def decompose_features(features, decomposer, n_components=None, lag_time=1):
'''
Decomposing features is a way to reduce the dimension of the features.
Each of the components is a eigenvector of the feature space, dimension: (n_features,)
The old features are transformed to the new feature space.
Consider one sample, which is vectorized to (n_features,).T,
apply the transform matrix, which is in the shape (n_components, n_features),
we will get its projection onto the new space (n_components,).
--------------------------------------------------------------------------------------------------------------------------------------
Input
features : array-like, length n_trajs, each of shape (n_samples, n_features)
Output
features_new : array-like, length n_trajs, each of shape (n_samples, n_components) ((n_samples, n_samples) if n_components = None)
dcmp.components_ : shape (n_components, n_features), ((n_samples, n_features) if n_components = None)
PCA : Principal axes in feature space, representing the directions of maximum variance in the data.
tICA : Components with maximum autocorrelation.
'''
if decomposer == 'PCA':
from msmbuilder.decomposition import PCA
dcmp = PCA(n_components=n_components)
elif decomposer == 'tICA':
from msmbuilder.decomposition import tICA
dcmp = tICA(n_components=n_components, lag_time=lag_time)
features_new = dcmp.fit_transform(features)
return features_new, dcmp.components_
def decompose_features(features, decomposer, n_components=None, lag_time=1):
'''
Input
features : list of arrays, length n_trajs, each of shape (n_samples, n_features)
Output
features_new : list of arrays, length n_trajs, each of shape (n_samples, n_features_new)
'''
if decomposer == 'PCA':
from msmbuilder.decomposition import PCA
dcmp = PCA(n_components=n_components)
elif decomposer == 'tICA':
from msmbuilder.decomposition import tICA
dcmp = tICA(n_components=n_components, lag_time=lag_time)
return dcmp.fit_transform(features)
def test_1():
#Compare msmbuilder.pca with sklearn.decomposition
pcar = PCAr()
pcar.fit(np.concatenate(trajs))
pca = PCA()
pca.fit(trajs)
y_ref1 = pcar.transform(trajs[0])
y1 = pca.transform(trajs)[0]
np.testing.assert_array_almost_equal(y_ref1, y1)
np.testing.assert_array_almost_equal(pca.components_, pcar.components_)
np.testing.assert_array_almost_equal(pca.explained_variance_,
pcar.explained_variance_)
np.testing.assert_array_almost_equal(pca.mean_, pcar.mean_)
np.testing.assert_array_almost_equal(pca.n_components_, pcar.n_components_)
np.testing.assert_array_almost_equal(pca.noise_variance_,
pcar.noise_variance_)
def test_generator():
# Check to see if it works with a generator
traj_dict = dict((i, t) for i, t in enumerate(trajs))
pcar = PCAr()
pcar.fit(np.concatenate(trajs))
pca = PCA()
# on python 3, dict.values() returns a generator
pca.fit(traj_dict.values())
y_ref1 = pcar.transform(trajs[0])
y1 = pca.transform(trajs)[0]
np.testing.assert_array_almost_equal(y_ref1, y1)
np.testing.assert_array_almost_equal(pca.components_, pcar.components_)
np.testing.assert_array_almost_equal(pca.explained_variance_,
pcar.explained_variance_)
np.testing.assert_array_almost_equal(pca.mean_, pcar.mean_)
np.testing.assert_array_almost_equal(pca.n_components_, pcar.n_components_)
np.testing.assert_array_almost_equal(pca.noise_variance_,
pcar.noise_variance_)
def test_2():
# Tet that PCA it works in a msmbuilder pipeline
p = Pipeline([('pca', PCA()), ('cluster', KCenters())])
p.fit(trajs)
def fit_pca(self):
self.pca = PCA(n_components=10)
self.pca.fit(self.seqs2d)
self.pcax = self.pca.transform(self.seqs2d)
