examples/triangle/triangle-zigzag.py
author Christos Mantoulidis <cmad@stanford.edu>
Tue, 04 Aug 2009 13:23:16 -0700
branchdev
changeset 156 f75fb57d2831
parent 112 f209958b5c17
child 149 3d15aca95dfb
permissions -rw-r--r--
Changed implementation of WeightedRips to store simplex values (max distance between simplices' vertices) as an invisible layer on top of each simplex object, so that the data() field of WeightedRips has been freed for use by the users again.

from dionysus import Simplex, ZigzagPersistence, \
                     vertex_cmp, data_cmp \
#                    ,enable_log

complex = {Simplex((0,),        0):     None,                   # A
           Simplex((1,),        1):     None,                   # B
           Simplex((2,),        2):     None,                   # C
           Simplex((0,1),       2.5):   None,                   # AB
           Simplex((1,2),       2.9):   None,                   # BC
           Simplex((0,2),       3.5):   None,                   # CA
           Simplex((0,1,2),     5):     None}                   # ABC

print "Complex:"
for s in sorted(complex.keys()): print s
print

#enable_log("topology/persistence")
zz = ZigzagPersistence()

# Add all the simplices
b = 1
for s in sorted(complex.keys(), data_cmp):
    print "%d: Adding %s" % (b, s)
    i,d = zz.add([complex[ss] for ss in s.boundary], b)
    complex[s] = i
    if d:   print "Interval (%d, %d)" % (d, b-1)
    b += 1

# Remove all the simplices
for s in sorted(complex.keys(), reverse = True):
    print "%d: Removing %s" % (b, s)
    d = zz.remove(complex[s], b)
    complex[s] = None
    if d:   print "Interval (%d, %d)" % (d, b-1)
    b += 1