class TransformationStorer:
def __init__(self, X, y):
# Initialize a fake NCA and variables needed to call the loss
# function:
self.fake_nca = NeighborhoodComponentsAnalysis()
self.fake_nca.n_iter_ = np.inf
self.X, y, _ = self.fake_nca._validate_params(X, y)
self.same_class_mask = y[:, np.newaxis] == y[np.newaxis, :]
def callback(self, transformation, n_iter):
"""Stores the last value of the transformation taken as input by
the optimizer"""
self.transformation = transformation
class LossStorer:
def __init__(self, X, y):
self.loss = np.inf # initialize the loss to very high
# Initialize a fake NCA and variables needed to compute the loss:
self.fake_nca = NeighborhoodComponentsAnalysis()
self.fake_nca.n_iter_ = np.inf
self.X, y, _ = self.fake_nca._validate_params(X, y)
self.same_class_mask = y[:, np.newaxis] == y[np.newaxis, :]
def callback(self, transformation, n_iter):
"""Stores the last value of the loss function"""
self.loss, _ = self.fake_nca._loss_grad_lbfgs(transformation,
self.X,
self.same_class_mask,
-1.0)