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#!/usr/bin/regina-python --nolibs
#
# Reads the given file and outputs a line for each triangulation.
# Each line contains two alphabetical strings, encoding the face gluings
# and the first homology group respectively.
#
# The face gluings are encoded using the Callahan-Hildebrand-Weeks
# dehydration format. The first homology group is encoded by a string
# of letters, where a..z represent 0..25 and A..Z represent 26..51.
# The first letter gives the rank of the group, and the remaining
# letters give the invariant factors.
import sys
if len(sys.argv) != 2:
print "Usage: " + sys.argv[0] + " <filename>"
sys.exit(1)
tree = regina.readFileMagic(sys.argv[1])
if not tree:
print "E: Could not open file " + sys.argv[1] + "."
print
print "Usage: " + sys.argv[0] + " <filename>"
sys.exit(1)
def encode(i):
if i < 0:
print 'ERROR: Negative integer:', i
sys.exit(1)
if i < 26:
return chr(ord('a') + i)
if i < 52:
return chr(ord('A') + i - 26)
print 'ERROR: Integer out of range:', i
sys.exit(1)
def grouprep(g):
ans = encode(g.getRank())
for i in range(g.getNumberOfInvariantFactors()):
ans = ans + encode(g.getInvariantFactor(i).longValue())
return ans
def process(tri):
dehydration = tri.dehydrate()
if dehydration == '':
print 'ERROR: No dehydration'
sys.exit(1)
print dehydration + ' ' + grouprep(tri.getHomologyH1())
sys.stdout.flush()
p = tree
while p != None:
if p.getPacketType() == regina.NTriangulation.packetType:
process(p)
p = p.nextTreePacket()
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