def transform(self, s):
""" Burrows-Wheeler transform with SuffixTree """
assert self.EOS not in s, "Input string cannot contain null character ('%s')" % self.EOS
# add end of text marker
s += self.EOS
st = SuffixTree()
# construct a suffix tree O(n * log n)
# can also be done in O(n) time
st.add(s)
# walk inorder to find sorted suffixes
# only get the length of each suffix
lens = self._walk(st.root)
# as the last column letter will be left of the suffix
# this means it's len(suffix) + 1
# from the end of the input string s
r = [0]*len(lens)
for i in xrange(len(lens)):
l = lens[i]
if l == len(lens):
r[i] = self.EOS
else:
r[i] = s[-l-1]
return ''.join(r)
def transform(self, s):
""" Burrows-Wheeler transform with SuffixTree """
assert self.EOS not in s, "Input string cannot contain null character ('%s')" % self.EOS
# add end of text marker
s += self.EOS
st = SuffixTree()
# construct a suffix tree O(n * log n)
# can also be done in O(n) time
st.add(s)
# walk inorder to find sorted suffixes
# only get the length of each suffix
lens = self._walk(st.root)
# as the last column letter will be left of the suffix
# this means it's len(suffix) + 1
# from the end of the input string s
r = [0] * len(lens)
for i in xrange(len(lens)):
l = lens[i]
if l == len(lens):
r[i] = self.EOS
else:
r[i] = s[-l - 1]
return ''.join(r)
'''
Created on Oct 23, 2018
@author: ckennington
'''
from stlm import STLM
from suffixtree import SuffixTree
from sequence import Sequence
trie = SuffixTree()
text = 'c a c a o'.split()
for w in text:
print('adding', w)
trie.add(w)
print('\n')
trie.print_tree()
print('\n')
trie.update_all_counts()
stlm = STLM(trie)
tests = [
'c a'.split(), 'c a o'.split(), 'a o'.split(), 'o'.split(), 'c'.split()
]
for test in tests:
seq = Sequence()
