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Diffstat (limited to 'python/src/simple_example.py')
-rw-r--r-- | python/src/simple_example.py | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/python/src/simple_example.py b/python/src/simple_example.py new file mode 100644 index 0000000..955e213 --- /dev/null +++ b/python/src/simple_example.py @@ -0,0 +1,55 @@ +"""This file contains a simple example that demonstrates the usage of the library interface""" + +if __name__ == "__main__": + + print(""" + we will build an ordered boundary matrix of this simplicial complex consisting of a single triangle: + + 3 + |\\ + | \\ + | \\ + | \\ 4 + 5| \\ + | \\ + | 6 \\ + | \\ + |________\\ + 0 2 1 + +""") + + import phat + + # define a boundary matrix with the chosen internal representation + boundary_matrix = phat.boundary_matrix(representation = phat.representations.vector_vector) + + # set the respective columns -- (dimension, boundary) pairs + boundary_matrix.columns = [ (0, []), + (0, []), + (1, [0,1]), + (0, []), + (1, [1,3]), + (1, [0,3]), + (2, [2,4,5])] + + # or equivalently, boundary_matrix = phat.boundary_matrix(representation = ..., columns = ...) + # would combine the creation of the matrix and the assignment of the columns + + # print some information of the boundary matrix: + print("\nThe boundary matrix has %d columns:" % len(boundary_matrix.columns)) + for col in boundary_matrix.columns: + s = "Column %d represents a cell of dimension %d." % (col.index, col.dimension) + if (col.boundary): + s = s + " Its boundary consists of the cells " + " ".join([str(c) for c in col.boundary]) + print(s) + print("Overall, the boundary matrix has %d entries." % len(boundary_matrix)) + + pairs = boundary_matrix.compute_persistence_pairs() + + pairs.sort() + + print("\nThere are %d persistence pairs: " % len(pairs)) + for pair in pairs: + print("Birth: %d, Death: %d" % pair) + |