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authorMathieuCarriere <mathieu.carriere3@gmail.com>2021-12-04 13:22:23 +0100
committerMathieuCarriere <mathieu.carriere3@gmail.com>2021-12-04 13:22:23 +0100
commit96c7e5ce2f0146798f66c89421b0d23e98a2a390 (patch)
treef42bd81a37c98c0d7937363a7fed5a1411cadc82 /src/python/gudhi/tensorflow/cubical_layer.py
parent979d12e00b4ea71391d132589ee3304e378459b9 (diff)
update code and doc
Diffstat (limited to 'src/python/gudhi/tensorflow/cubical_layer.py')
-rw-r--r--src/python/gudhi/tensorflow/cubical_layer.py20
1 files changed, 14 insertions, 6 deletions
diff --git a/src/python/gudhi/tensorflow/cubical_layer.py b/src/python/gudhi/tensorflow/cubical_layer.py
index 8fe9cff0..b16c512f 100644
--- a/src/python/gudhi/tensorflow/cubical_layer.py
+++ b/src/python/gudhi/tensorflow/cubical_layer.py
@@ -8,7 +8,7 @@ from ..cubical_complex import CubicalComplex
# The parameters of the model are the pixel values.
-def _Cubical(Xflat, Xdim, dimensions, min_persistence):
+def _Cubical(Xflat, Xdim, dimensions):
# Parameters: Xflat (flattened image),
# Xdim (shape of non-flattened image)
# dimensions (homology dimensions)
@@ -16,7 +16,7 @@ def _Cubical(Xflat, Xdim, dimensions, min_persistence):
# Compute the persistence pairs with Gudhi
# We reverse the dimensions because CubicalComplex uses Fortran ordering
cc = CubicalComplex(dimensions=Xdim[::-1], top_dimensional_cells=Xflat)
- cc.compute_persistence(min_persistence=min_persistence)
+ cc.compute_persistence()
# Retrieve and ouput image indices/pixels corresponding to positive and negative simplices
cof_pp = cc.cofaces_of_persistence_pairs()
@@ -37,17 +37,19 @@ class CubicalLayer(tf.keras.layers.Layer):
"""
TensorFlow layer for computing cubical persistence out of a cubical complex
"""
- def __init__(self, dimensions, min_persistence=0., **kwargs):
+ def __init__(self, dimensions, min_persistence=None, **kwargs):
"""
Constructor for the CubicalLayer class
Parameters:
dimensions (List[int]): homology dimensions
+ min_persistence (List[float]): minimum distance-to-diagonal of the points in the output persistence diagrams (default None, in which case 0. is used for all dimensions)
"""
super().__init__(dynamic=True, **kwargs)
self.dimensions = dimensions
- self.min_persistence = min_persistence
-
+ self.min_persistence = min_persistence if min_persistence != None else [0. for _ in range(len(self.dimensions))]
+ assert len(self.min_persistence) == len(self.dimensions)
+
def call(self, X):
"""
Compute persistence diagram associated to a cubical complex filtered by some pixel values
@@ -62,7 +64,13 @@ class CubicalLayer(tf.keras.layers.Layer):
# Don't compute gradient for this operation
Xflat = tf.reshape(X, [-1])
Xdim = X.shape
- indices = _Cubical(Xflat.numpy(), Xdim, self.dimensions, self.min_persistence)
+ indices = _Cubical(Xflat.numpy(), Xdim, self.dimensions)
# Get persistence diagram by simply picking the corresponding entries in the image
self.dgms = [tf.reshape(tf.gather(Xflat, indice), [-1,2]) for indice in indices]
+ for idx_dim in range(len(self.min_persistence)):
+ min_pers = self.min_persistence[idx_dim]
+ if min_pers >= 0:
+ finite_dgm = self.dgms[idx_dim]
+ persistent_indices = np.argwhere(np.abs(finite_dgm[:,1]-finite_dgm[:,0]) > min_pers).ravel()
+ self.dgms[idx_dim] = tf.gather(finite_dgm, indices=persistent_indices)
return self.dgms