Merge master and fix conflicts

1 files changed, 53 insertions, 0 deletions

diff --git a/src/python/doc/ls_simplex_tree_tflow_itf_ref.rst b/src/python/doc/ls_simplex_tree_tflow_itf_ref.rst
new file mode 100644
index 00000000..9d7d633f
--- /dev/null
+++ b/src/python/doc/ls_simplex_tree_tflow_itf_ref.rst
@@ -0,0 +1,53 @@
+:orphan:
+
+.. To get rid of WARNING: document isn't included in any toctree
+
+TensorFlow layer for lower-star persistence on simplex trees
+############################################################
+
+.. include:: differentiation_sum.inc
+
+Example of gradient computed from lower-star filtration of a simplex tree
+-------------------------------------------------------------------------
+
+.. testcode::
+
+    from gudhi.tensorflow import LowerStarSimplexTreeLayer
+    import tensorflow as tf
+    import gudhi as gd
+
+    st = gd.SimplexTree()
+    st.insert([0, 1]) 
+    st.insert([1, 2]) 
+    st.insert([2, 3]) 
+    st.insert([3, 4]) 
+    st.insert([4, 5]) 
+    st.insert([5, 6]) 
+    st.insert([6, 7]) 
+    st.insert([7, 8]) 
+    st.insert([8, 9]) 
+    st.insert([9, 10]) 
+
+    F = tf.Variable([6.,4.,3.,4.,5.,4.,3.,2.,3.,4.,5.], dtype=tf.float32, trainable=True)
+    sl = LowerStarSimplexTreeLayer(simplextree=st, homology_dimensions=[0])
+
+    with tf.GradientTape() as tape:
+        dgm = sl.call(F)[0][0]
+        loss = tf.math.reduce_sum(tf.square(.5*(dgm[:,1]-dgm[:,0])))
+
+    grads = tape.gradient(loss, [F])
+    print(grads[0].indices.numpy())
+    print(grads[0].values.numpy())
+
+.. testoutput::
+
+    [2 4]
+    [-1.  1.]
+
+Documentation for LowerStarSimplexTreeLayer
+-------------------------------------------
+
+.. autoclass:: gudhi.tensorflow.LowerStarSimplexTreeLayer
+   :members:
+   :special-members: __init__
+   :show-inheritance: