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#._cv_part guppy.etc.RE_Rect
""" Support functions for RE simplification.
This module is intended for use by the RE module.
It is in a separate module to keep RE itself cleaner
since the algorithm, 'rectangle selection', is a quite
separate part that depends on some tricky heuristics.
The primary entry function is
chooserects(lines, gauges, trace)
It chooses 'the best' rectangles from lines to base simplification on.
A weight on atoms is given by gauges.
The trace parameter is for debugging.
pr() gives some example usages of chooserects.
"""
from guppy.sets import immbitset, mutbitset, immbitrange
class Rect(object):
__slots__ = 'width', 'lines', 'gainmemo', 'lnos', 'all_lines', 'common_part'
def __init__(self, width, lines):
self.width = width
self.lines = lines
assert not (width and len(lines) == 1)
self.gainmemo = {}
def init2(self, lnobyid, all_lines):
self.all_lines = all_lines
self.lnos = immbitset([lnobyid[id(line)] for line in self.lines])
self.common_part = self.get_common_part()
def reducelines(self, lnos):
# Reduce lines of self by removing some lines
# Argument: lnos, a 'set' of line numbers to remove
olnos = self.lnos
lnos = olnos & ~lnos
if lnos != olnos:
self.lnos = lnos
self.lines = [self.all_lines[lno] for lno in lnos]
if len(lnos) == 1:
self.width = len(self.lines[0])
def get_lines(self, pickednos = 0):
lines = []
for i in self.lnos & ~ pickednos:
lines.append(self.all_lines[i])
return lines
def __str__(self):
return '<\n dir = %d\n width = %d\n lnos = %s\n lines = %s\n>'%(
self.dir, self.width, list(self.lnos), self.lines)
__repr__=__str__
class LeftRect(Rect):
__slots__ = ()
dir = 0
def get_common_part(self):
return self.lines[0][:self.width]
def get_uncommons(self, pickednos=0):
uc = []
for line in self.get_lines(pickednos):
uc.append(line[self.width:])
return uc
class RightRect(Rect, object):
__slots__ = ()
dir = -1
def get_common_part(self):
lo = -self.width
if lo == 0:
return []
return self.lines[0][lo:]
def get_uncommons(self, pickednos=0):
uc = []
hi = -self.width
if hi == 0:
hi = None
for line in self.get_lines(pickednos):
uc.append(line[:hi])
return uc
def sum_gauge(gauge, lst):
global hits, misses
if gauge is None:
return len(lst)
else:
gain = 0
for x in lst:
gain += gauge(x)
return gain
def cmp_gauged(xs, ys, gauges):
for gauge in gauges:
gx = sum_gauge(gauge, xs)
gy = sum_gauge(gauge, ys)
c = cmp(gx, gy)
if c:
return c
return 0
class InducedRect:
def __init__(self, s, lines, lnos):
self.s = s
self.width = s.width
self.all_lines = s.all_lines
self.lines = lines
self.lnos = lnos
class InducedRightRect(InducedRect, RightRect):
pass
class InducedLeftRect(InducedRect, LeftRect):
pass
def brect(lines):
if len(lines) <= 1:
return [LeftRect(0, lines)]
newrects = [LeftRect(0, lines), RightRect(0, lines)]
donerects = []
while newrects:
oldrects = newrects
newrects = []
for r in oldrects:
width = r.width
while 1:
is_done = 0
d = {}
pos = width ^ r.dir
for line in r.lines:
if width < len(line):
d.setdefault(line[pos], []).append(line)
else:
is_done = 1
if is_done or len(d) != 1:
break
r.width = width = width + 1
donerects.append(r)
width += 1
for k, v in d.items():
if len(v) > 1:
new_r = r.__class__(width, v)
newrects.append(new_r)
return donerects
def choose(rects, lines = [], gauges = [None], trace=''):
def induce(r):
if trace == 'induce':
pdb.set_trace()
uncommons = r.get_uncommons()
if len(uncommons) < 2:
return
irs = []
for s in rects:
if s.dir != r.dir:
continue
pss = []
uncs = s.get_uncommons(pickednos)
lnos = s.lnos & ~pickednos
assert len(uncs) == len(lnos)
for unc, lno in zip(uncs, lnos):
if unc in uncommons:
pss.append(lno)
if len(pss) == len(uncommons):
pslnos = immbitset(pss)
pss = [lines[lno] for lno in pss]
if s.dir == -1:
c = InducedRightRect
else:
c = InducedLeftRect
ir = c(s, pss, pslnos)
if trace == 'indap':
pdb.set_trace()
irs.append(ir)
if irs:
#pdb.set_trace()
news.extend(irs)
def overlap(r):
#
if 'overlap' in trace:
pdb.set_trace()
rlnos = r.lnos
tonews = []
for s in rects:
if s is r:
continue
if s.dir != r.dir:
continue
slnos = s.lnos
if not (slnos & rlnos):
continue
slnos &= ~ pickednos
if not slnos:
# remove
continue
scom = s.common_part
if not scom:
continue
for t in rects:
if t is s:
continue
if t.dir == s.dir:
continue
tlnos = t.lnos & ~pickednos
if (tlnos & rlnos):
continue
olnos = tlnos & slnos
if not olnos:
continue
if slnos == tlnos:
continue
tcom = t.common_part
if not tcom:
continue
c = cmp_gauged(scom, tcom, gauges)
if c > 0:
continue
if trace == 'obreak':
pdb.set_trace
break
else:
# s is ok
tonews.append(s)
rects.remove(s)
if len(tonews) > 1:
pdb.set_trace()
news.extend(tonews)
def picknext():
while 1:
if news:
if trace == 'news':
pdb.set_trace()
r = news[0]
del news[0]
else:
r = None
for s in list(rects):
slnos = s.lnos - pickednos
if not slnos:
rects.remove(s)
continue
sn = len(slnos) - 1
sw = s.width
if r is not None:
if not sw:
break
if not sn:
continue
if rwn:
rmemo = r.gainmemo
smemo = s.gainmemo
c = 0
for gauge in gauges:
try:
gr = rmemo[gauge]
except KeyError:
gr = sum_gauge(gauge, r.common_part)
rmemo[gauge] = gr
gr *= rn
try:
gs = smemo[gauge]
except KeyError:
gs = sum_gauge(gauge, s.common_part)
smemo[gauge] = gs
gs *= sn
c = gr - gs
if c:
break
if c >= 0:
continue
r = s
rlnos = slnos
if not sw:
break
rn = sn
rw = sw
rwn = sn * sw
if r is not None:
rects.remove(r)
if r is not None:
r.reducelines(pickednos)
if r.lnos:
return r
def cmpinit(x, y):
wx = x.width
wy = y.width
c = wy - wx
if c:
return c
c = y.dir - x.dir
if c:
return c
c = cmp(x.lnos[0], y.lnos[0])
return c
if gauges[0] == None:
gauges = gauges[1:]
lnobyid = dict([(id(line), i) for i, line in enumerate(lines)])
orects = rects
rects = list(orects)
for r in rects:
r.init2(lnobyid, lines)
rects.sort(cmpinit)
allnos = immbitrange(len(lines))
pickednos = mutbitset()
pickedrects = []
news = []
while pickednos != allnos:
r = picknext()
pickednos |= r.lnos
pickedrects.append(r)
induce(r)
if trace == 'induced':
pdb.set_trace()
overlap(r)
if trace == 'chosorted':
pdb.set_trace()
if trace == 'choosen':
pdb.set_trace()
return pickedrects
def chooserects(lines, gauges = [None], trace=''):
rects = brect(lines)
choosen = choose(rects, lines, gauges, trace)
return choosen
def pr():
x = chooserects(['abc','ade'])
x = chooserects(['abc',
'abe',
'ace',
'xby'])
print x
x = chooserects(['ab1',
'ab2',
'ac3',
'ac4'])
print x
# Case where.. (from right).. :
# the total gain of two rects (bfbf+cfcf = 4) is greater than the gain of another
# overlapping rect (ffff == 3), although the individual gains are less (= 2).
# But in this case at least, the end result should likely become the same
x = chooserects([
'1bf',
'2bf',
'3cf',
'4cf'])
print x
# Case where it chooses twice..
x = chooserects([
'abc',
'abd',
'bcx',
'bdy'
])
print 'TW',x
# Case where it didn't choose enough rects
x = ([
'abc',
'abd',
'e'
])
print chooserects(x)
# Case where it should prefer one side or the other
# i.e. left traditionally
print chooserects(['abc','axc'])
# Case where it should give a width 0 rect
print chooserects(['a',''])
# Case with overlap
print chooserects(['abcd','abce','a','f'])
# Case with induce
print chooserects(['abcd','abce','d','e'])
print chooserects(['auvw', 'buvw', 'a', 'b'])
print chooserects(['axuvw','bxuvw','axy','bxy','cy'])
# Case with overlap reversed as per Mar 4
print chooserects(['dcba','ecba','a','f'], trace='choosen')
def tmany():
for i in range(100):
x = chooserects(['abc',
'abe',
'ace',
'xby'])
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