def test():
stree = GeneralisedSuffixTree(['mississippi'])
for shared in stree.sharedSubstrings(2):
for seq, start, stop in shared:
print seq, '[' + str(start) + ':' + str(stop) + ']',
print stree.sequences[seq][start:stop],
print stree.sequences[seq][:start] + '|' + stree.sequences[seq][
start:stop] + '|' + stree.sequences[seq][stop:]
def getMAXchSTR(string):
stree = GeneralisedSuffixTree([string])
## record the max length of shared substring and the substring
maxlength = 0
register = ""
for shared in stree.sharedSubstrings(15): ## five chinese characters
for seq, start, stop in shared:
if (stop - start) > maxlength:
maxlength = stop - start
register = stree.sequences[seq][start:stop]
#print type(register),register.decode('utf8')
return maxlength, register
def main():
with open(sys.argv[1], 'r') as fi:
seq_1 = fi.readline().strip()
seq_2 = fi.readline().strip()
seqs = [seq_1, seq_2]
stree = GeneralisedSuffixTree(seqs)
max_len = 0
max_str = ''
for shared in stree.sharedSubstrings():
for seq, start, stop in shared:
cs = seqs[seq][start:stop]
if len(cs) > max_len:
max_len = len(cs)
max_str = cs
print(max_str)
def __computeLCS(self, stringList):
'''
Returns a one-element list containing the LCS of the input stringList
'''
alphabet = self.__getAlphabet(
stringList) # get alphabet of (all characters in) stringList
# check if alphabet requires too many characters to create enough terminal characters
# for each string in stringList
if not self.__isComputable(stringList, alphabet):
strLstLen = len(stringList)
return self.__computeLCS(self.__computeLCS(stringList[0:strLstLen/2]) + \
self.__computeLCS(stringList[strLstLen/2:strLstLen]))
(stringList, translationDict) = self.__translateCharacters(
stringList, alphabet) # translate characters in stringList
# make suffix tree
stree = GeneralisedSuffixTree(stringList)
# get all shared substrings
sharedSubstrings = []
for shared in stree.sharedSubstrings():
for seq, start, stop in shared:
sharedSubstrings += [stree.sequences[seq][start:stop]]
# find the index of the longest shared substring
substringLens = [len(substring) for substring in sharedSubstrings]
if substringLens == []:
lcs = [""]
return lcs
longestSubstringIndex = substringLens.index(max(substringLens))
lcs = sharedSubstrings[longestSubstringIndex]
# Back translate
for (translatedChar, originalChar) in translationDict.iteritems():
lcs = lcs.replace(translatedChar, originalChar)
return [lcs]
import sys
out = open("output.txt", 'w')
Input = open(sys.argv[1], 'r').read().split("\n")
text1 = Input[0].strip()
text2 = Input[1].strip()
from suffix_tree import GeneralisedSuffixTree
stree = GeneralisedSuffixTree([text1, text2])
max_len = 0
for shared in stree.sharedSubstrings():
seq, start, stop = shared[0]
if (stop - start) > max_len:
max_len = stop - start
longestSS = stree.sequences[seq][start:stop]
print >> out, longestSS
baseComplement = {'A': 'T', 'C': 'G', 'G': 'C', 'T': 'A'}
def revc(seq):
return "".join([baseComplement[base] for base in seq[::-1]])
# Build a random string, which should have some short reverse complements already.
bases = ['A', 'C', 'G', 'T']
data = ''.join(choice(bases) for i in xrange(400000))
#data = "AGGGTTTCCCTGACCTTCACTGCAGGTCATGCA"
# revc TGCATGACCTGCAGTGAAGGTCAGGGAAACCCT
# 012345678901234567890123456789012
# 1 2 3
print "Got data"
revdata = revc(data)
print "Got reverse data"
n = len(data)
minlength = 18
tree = GeneralisedSuffixTree([data, revdata])
for shared in tree.sharedSubstrings(minlength):
_, start, stop = shared[0]
seq = data[start:stop]
_, rstart, rstop = shared[1]
rseq = data[n - rstop:n - rstart]
print "Match: {0} at [{1}:{2}] and {3} at [{4}:{5}]".format(
seq, start, stop, rseq, n - rstop, n - rstart)
#!/usr/bin/env python
# -*- coding: utf-8 -*-
from suffix_tree import GeneralisedSuffixTree
# s1 = u'mississippi'
# s2 = u'sippissi'
s1 = u'一寸光阴一寸金';
s2 = u'寸金难买寸光阴';
stree = GeneralisedSuffixTree([s1,s2])
for shared in stree.sharedSubstrings(2):
print '-'*70
for (seq,start,stop) in shared:
print seq,
print '['+str(start)+':'+str(stop)+']',
ss = stree.sequences[seq][start:stop]
print ss.encode('utf-8'),
at = stree.sequences[seq][:start]+\
'{'+stree.sequences[seq][start:stop]+'}'+\
stree.sequences[seq][stop:]
print at.encode('utf-8')
print '='*70
def validateSubstring(strings, seq):
for s in strings:
if s.find(seq) == -1:
return False
return True
with open('rosalind_lcs.txt') as spec:
data = [seq.strip() for seq in spec]
# The generalized suffix tree doesn't work well with a large number of strings.
# Use the first 10 to generate candidates, and then compare each candidate
# (in decreasing length order) to the data to find a common substring.
tree = GeneralisedSuffixTree(data[:10])
candidates = []
for shared in tree.sharedSubstrings(5):
for seq, start, stop in shared:
candidates.append(tree.sequences[seq][start:stop])
break
candidates.sort(cmp=None, key=lambda s: len(s), reverse=True)
for c in candidates:
if validateSubstring(data, c):
print c
print len(c)
break
else:
print "No common string found!"
