examples/alphashapes/alphashapes.py
 author Dmitriy Morozov Wed, 16 Dec 2009 15:39:06 -0800 branch dev changeset 179 d15c6d144645 parent 131 d9e050258358 child 181 1ee6edc17cb6 permissions -rw-r--r--
Resurrected vineyard code: * Switched StaticPersistence + (serializable) Filtration to Boost.MultiIndex * Updated DynamicPersistenceTrails to work with the new MultiIndex way * Created LSVineyard class, and fixed the grid examples
```
# Computes the persistence diagram of the alpha shapes in both 2D and 3D
# (decided dynamically based on the input file)

from    dionysus        import Filtration, StaticPersistence, data_dim_cmp, vertex_cmp, \
fill_alpha3D_complex, fill_alpha2D_complex, points_file
from    sys             import argv, exit
from    math            import sqrt

if len(argv) < 2:
print "Usage: %s POINTS" % argv[0]
exit()

points = [p for p in points_file(argv[1])]
simplices = []
if   len(points[0]) == 2:           # 2D
fill_alpha2D_complex(points, simplices)
elif len(points[1]) == 3:           # 3D
fill_alpha3D_complex(points, simplices)

simplices.sort(vertex_cmp)                      # Must ensure lexicographic ordering
print "Total number of simplices:", len(simplices)

f = Filtration(simplices, data_dim_cmp)
print "Filtration initialized"

p = StaticPersistence(f)
print "StaticPersistence initialized"

p.pair_simplices()
print "Simplices paired"

print "Outputting persistence diagram"
for i in p:
if i.sign():
b = simplices[f[p(i)]]
if i == i.pair:
print b.dimension(), sqrt(b.data), "inf"
continue

d = simplices[f[p(i.pair)]]
print b.dimension(), sqrt(b.data), sqrt(d.data)
```