1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812
|
#
# (re)generate unicode property and type databases
#
# this script converts a unicode 3.2 database file to
# Modules/unicodedata_db.h, Modules/unicodename_db.h,
# and Objects/unicodetype_db.h
#
# history:
# 2000-09-24 fl created (based on bits and pieces from unidb)
# 2000-09-25 fl merged tim's splitbin fixes, separate decomposition table
# 2000-09-25 fl added character type table
# 2000-09-26 fl added LINEBREAK, DECIMAL, and DIGIT flags/fields (2.0)
# 2000-11-03 fl expand first/last ranges
# 2001-01-19 fl added character name tables (2.1)
# 2001-01-21 fl added decomp compression; dynamic phrasebook threshold
# 2002-09-11 wd use string methods
# 2002-10-18 mvl update to Unicode 3.2
# 2002-10-22 mvl generate NFC tables
# 2002-11-24 mvl expand all ranges, sort names version-independently
# 2002-11-25 mvl add UNIDATA_VERSION
# 2004-05-29 perky add east asian width information
#
# written by Fredrik Lundh (fredrik@pythonware.com)
#
import sys
SCRIPT = sys.argv[0]
VERSION = "2.3"
# The Unicode Database
UNIDATA_VERSION = "3.2.0"
UNICODE_DATA = "UnicodeData.txt"
COMPOSITION_EXCLUSIONS = "CompositionExclusions.txt"
EASTASIAN_WIDTH = "EastAsianWidth.txt"
CATEGORY_NAMES = [ "Cn", "Lu", "Ll", "Lt", "Mn", "Mc", "Me", "Nd",
"Nl", "No", "Zs", "Zl", "Zp", "Cc", "Cf", "Cs", "Co", "Cn", "Lm",
"Lo", "Pc", "Pd", "Ps", "Pe", "Pi", "Pf", "Po", "Sm", "Sc", "Sk",
"So" ]
BIDIRECTIONAL_NAMES = [ "", "L", "LRE", "LRO", "R", "AL", "RLE", "RLO",
"PDF", "EN", "ES", "ET", "AN", "CS", "NSM", "BN", "B", "S", "WS",
"ON" ]
EASTASIANWIDTH_NAMES = [ "F", "H", "W", "Na", "A", "N" ]
# note: should match definitions in Objects/unicodectype.c
ALPHA_MASK = 0x01
DECIMAL_MASK = 0x02
DIGIT_MASK = 0x04
LOWER_MASK = 0x08
LINEBREAK_MASK = 0x10
SPACE_MASK = 0x20
TITLE_MASK = 0x40
UPPER_MASK = 0x80
def maketables(trace=0):
print "--- Reading", UNICODE_DATA, "..."
unicode = UnicodeData(UNICODE_DATA, COMPOSITION_EXCLUSIONS,
EASTASIAN_WIDTH)
print len(filter(None, unicode.table)), "characters"
makeunicodename(unicode, trace)
makeunicodedata(unicode, trace)
makeunicodetype(unicode, trace)
# --------------------------------------------------------------------
# unicode character properties
def makeunicodedata(unicode, trace):
dummy = (0, 0, 0, 0, 0)
table = [dummy]
cache = {0: dummy}
index = [0] * len(unicode.chars)
FILE = "Modules/unicodedata_db.h"
print "--- Preparing", FILE, "..."
# 1) database properties
for char in unicode.chars:
record = unicode.table[char]
if record:
# extract database properties
category = CATEGORY_NAMES.index(record[2])
combining = int(record[3])
bidirectional = BIDIRECTIONAL_NAMES.index(record[4])
mirrored = record[9] == "Y"
eastasianwidth = EASTASIANWIDTH_NAMES.index(record[15])
item = (
category, combining, bidirectional, mirrored, eastasianwidth
)
# add entry to index and item tables
i = cache.get(item)
if i is None:
cache[item] = i = len(table)
table.append(item)
index[char] = i
# 2) decomposition data
decomp_data = [0]
decomp_prefix = [""]
decomp_index = [0] * len(unicode.chars)
decomp_size = 0
comp_pairs = []
comp_first = [None] * len(unicode.chars)
comp_last = [None] * len(unicode.chars)
for char in unicode.chars:
record = unicode.table[char]
if record:
if record[5]:
decomp = record[5].split()
# prefix
if decomp[0][0] == "<":
prefix = decomp.pop(0)
else:
prefix = ""
try:
i = decomp_prefix.index(prefix)
except ValueError:
i = len(decomp_prefix)
decomp_prefix.append(prefix)
prefix = i
assert prefix < 256
# content
decomp = [prefix + (len(decomp)<<8)] +\
map(lambda s: int(s, 16), decomp)
# Collect NFC pairs
if not prefix and len(decomp) == 3 and \
char not in unicode.exclusions and \
unicode.table[decomp[1]][3] == "0":
p, l, r = decomp
comp_first[l] = 1
comp_last[r] = 1
comp_pairs.append((l,r,char))
try:
i = decomp_data.index(decomp)
except ValueError:
i = len(decomp_data)
decomp_data.extend(decomp)
decomp_size = decomp_size + len(decomp) * 2
else:
i = 0
decomp_index[char] = i
f = l = 0
comp_first_ranges = []
comp_last_ranges = []
prev_f = prev_l = None
for i in unicode.chars:
if comp_first[i] is not None:
comp_first[i] = f
f += 1
if prev_f is None:
prev_f = (i,i)
elif prev_f[1]+1 == i:
prev_f = prev_f[0],i
else:
comp_first_ranges.append(prev_f)
prev_f = (i,i)
if comp_last[i] is not None:
comp_last[i] = l
l += 1
if prev_l is None:
prev_l = (i,i)
elif prev_l[1]+1 == i:
prev_l = prev_l[0],i
else:
comp_last_ranges.append(prev_l)
prev_l = (i,i)
comp_first_ranges.append(prev_f)
comp_last_ranges.append(prev_l)
total_first = f
total_last = l
comp_data = [0]*(total_first*total_last)
for f,l,char in comp_pairs:
f = comp_first[f]
l = comp_last[l]
comp_data[f*total_last+l] = char
print len(table), "unique properties"
print len(decomp_prefix), "unique decomposition prefixes"
print len(decomp_data), "unique decomposition entries:",
print decomp_size, "bytes"
print total_first, "first characters in NFC"
print total_last, "last characters in NFC"
print len(comp_pairs), "NFC pairs"
print "--- Writing", FILE, "..."
fp = open(FILE, "w")
print >>fp, "/* this file was generated by %s %s */" % (SCRIPT, VERSION)
print >>fp
print >>fp, '#define UNIDATA_VERSION "%s"' % UNIDATA_VERSION
print >>fp, "/* a list of unique database records */"
print >>fp, \
"const _PyUnicode_DatabaseRecord _PyUnicode_Database_Records[] = {"
for item in table:
print >>fp, " {%d, %d, %d, %d, %d}," % item
print >>fp, "};"
print >>fp
print >>fp, "/* Reindexing of NFC first characters. */"
print >>fp, "#define TOTAL_FIRST",total_first
print >>fp, "#define TOTAL_LAST",total_last
print >>fp, "struct reindex{int start;short count,index;};"
print >>fp, "struct reindex nfc_first[] = {"
for start,end in comp_first_ranges:
print >>fp," { %d, %d, %d}," % (start,end-start,comp_first[start])
print >>fp," {0,0,0}"
print >>fp,"};\n"
print >>fp, "struct reindex nfc_last[] = {"
for start,end in comp_last_ranges:
print >>fp," { %d, %d, %d}," % (start,end-start,comp_last[start])
print >>fp," {0,0,0}"
print >>fp,"};\n"
# FIXME: <fl> the following tables could be made static, and
# the support code moved into unicodedatabase.c
print >>fp, "/* string literals */"
print >>fp, "const char *_PyUnicode_CategoryNames[] = {"
for name in CATEGORY_NAMES:
print >>fp, " \"%s\"," % name
print >>fp, " NULL"
print >>fp, "};"
print >>fp, "const char *_PyUnicode_BidirectionalNames[] = {"
for name in BIDIRECTIONAL_NAMES:
print >>fp, " \"%s\"," % name
print >>fp, " NULL"
print >>fp, "};"
print >>fp, "const char *_PyUnicode_EastAsianWidthNames[] = {"
for name in EASTASIANWIDTH_NAMES:
print >>fp, " \"%s\"," % name
print >>fp, " NULL"
print >>fp, "};"
print >>fp, "static const char *decomp_prefix[] = {"
for name in decomp_prefix:
print >>fp, " \"%s\"," % name
print >>fp, " NULL"
print >>fp, "};"
# split record index table
index1, index2, shift = splitbins(index, trace)
print >>fp, "/* index tables for the database records */"
print >>fp, "#define SHIFT", shift
Array("index1", index1).dump(fp, trace)
Array("index2", index2).dump(fp, trace)
# split decomposition index table
index1, index2, shift = splitbins(decomp_index, trace)
print >>fp, "/* decomposition data */"
Array("decomp_data", decomp_data).dump(fp, trace)
print >>fp, "/* index tables for the decomposition data */"
print >>fp, "#define DECOMP_SHIFT", shift
Array("decomp_index1", index1).dump(fp, trace)
Array("decomp_index2", index2).dump(fp, trace)
index, index2, shift = splitbins(comp_data, trace)
print >>fp, "/* NFC pairs */"
print >>fp, "#define COMP_SHIFT", shift
Array("comp_index", index).dump(fp, trace)
Array("comp_data", index2).dump(fp, trace)
fp.close()
# --------------------------------------------------------------------
# unicode character type tables
def makeunicodetype(unicode, trace):
FILE = "Objects/unicodetype_db.h"
print "--- Preparing", FILE, "..."
# extract unicode types
dummy = (0, 0, 0, 0, 0, 0)
table = [dummy]
cache = {0: dummy}
index = [0] * len(unicode.chars)
for char in unicode.chars:
record = unicode.table[char]
if record:
# extract database properties
category = record[2]
bidirectional = record[4]
flags = 0
if category in ["Lm", "Lt", "Lu", "Ll", "Lo"]:
flags |= ALPHA_MASK
if category == "Ll":
flags |= LOWER_MASK
if category == "Zl" or bidirectional == "B":
flags |= LINEBREAK_MASK
if category == "Zs" or bidirectional in ("WS", "B", "S"):
flags |= SPACE_MASK
if category == "Lt":
flags |= TITLE_MASK
if category == "Lu":
flags |= UPPER_MASK
# use delta predictor for upper/lower/title
if record[12]:
upper = int(record[12], 16) - char
assert -32768 <= upper <= 32767
upper = upper & 0xffff
else:
upper = 0
if record[13]:
lower = int(record[13], 16) - char
assert -32768 <= lower <= 32767
lower = lower & 0xffff
else:
lower = 0
if record[14]:
title = int(record[14], 16) - char
assert -32768 <= lower <= 32767
title = title & 0xffff
else:
title = 0
# decimal digit, integer digit
decimal = 0
if record[6]:
flags |= DECIMAL_MASK
decimal = int(record[6])
digit = 0
if record[7]:
flags |= DIGIT_MASK
digit = int(record[7])
item = (
upper, lower, title, decimal, digit, flags
)
# add entry to index and item tables
i = cache.get(item)
if i is None:
cache[item] = i = len(table)
table.append(item)
index[char] = i
print len(table), "unique character type entries"
print "--- Writing", FILE, "..."
fp = open(FILE, "w")
print >>fp, "/* this file was generated by %s %s */" % (SCRIPT, VERSION)
print >>fp
print >>fp, "/* a list of unique character type descriptors */"
print >>fp, "const _PyUnicode_TypeRecord _PyUnicode_TypeRecords[] = {"
for item in table:
print >>fp, " {%d, %d, %d, %d, %d, %d}," % item
print >>fp, "};"
print >>fp
# split decomposition index table
index1, index2, shift = splitbins(index, trace)
print >>fp, "/* type indexes */"
print >>fp, "#define SHIFT", shift
Array("index1", index1).dump(fp, trace)
Array("index2", index2).dump(fp, trace)
fp.close()
# --------------------------------------------------------------------
# unicode name database
def makeunicodename(unicode, trace):
FILE = "Modules/unicodename_db.h"
print "--- Preparing", FILE, "..."
# collect names
names = [None] * len(unicode.chars)
for char in unicode.chars:
record = unicode.table[char]
if record:
name = record[1].strip()
if name and name[0] != "<":
names[char] = name + chr(0)
print len(filter(lambda n: n is not None, names)), "distinct names"
# collect unique words from names (note that we differ between
# words inside a sentence, and words ending a sentence. the
# latter includes the trailing null byte.
words = {}
n = b = 0
for char in unicode.chars:
name = names[char]
if name:
w = name.split()
b = b + len(name)
n = n + len(w)
for w in w:
l = words.get(w)
if l:
l.append(None)
else:
words[w] = [len(words)]
print n, "words in text;", b, "bytes"
wordlist = words.items()
# sort on falling frequency, then by name
def cmpwords((aword, alist),(bword, blist)):
r = -cmp(len(alist),len(blist))
if r:
return r
return cmp(aword, bword)
wordlist.sort(cmpwords)
# figure out how many phrasebook escapes we need
escapes = 0
while escapes * 256 < len(wordlist):
escapes = escapes + 1
print escapes, "escapes"
short = 256 - escapes
assert short > 0
print short, "short indexes in lexicon"
# statistics
n = 0
for i in range(short):
n = n + len(wordlist[i][1])
print n, "short indexes in phrasebook"
# pick the most commonly used words, and sort the rest on falling
# length (to maximize overlap)
wordlist, wordtail = wordlist[:short], wordlist[short:]
wordtail.sort(lambda a, b: len(b[0])-len(a[0]))
wordlist.extend(wordtail)
# generate lexicon from words
lexicon_offset = [0]
lexicon = ""
words = {}
# build a lexicon string
offset = 0
for w, x in wordlist:
# encoding: bit 7 indicates last character in word (chr(128)
# indicates the last character in an entire string)
ww = w[:-1] + chr(ord(w[-1])+128)
# reuse string tails, when possible
o = lexicon.find(ww)
if o < 0:
o = offset
lexicon = lexicon + ww
offset = offset + len(w)
words[w] = len(lexicon_offset)
lexicon_offset.append(o)
lexicon = map(ord, lexicon)
# generate phrasebook from names and lexicon
phrasebook = [0]
phrasebook_offset = [0] * len(unicode.chars)
for char in unicode.chars:
name = names[char]
if name:
w = name.split()
phrasebook_offset[char] = len(phrasebook)
for w in w:
i = words[w]
if i < short:
phrasebook.append(i)
else:
# store as two bytes
phrasebook.append((i>>8) + short)
phrasebook.append(i&255)
assert getsize(phrasebook) == 1
#
# unicode name hash table
# extract names
data = []
for char in unicode.chars:
record = unicode.table[char]
if record:
name = record[1].strip()
if name and name[0] != "<":
data.append((name, char))
# the magic number 47 was chosen to minimize the number of
# collisions on the current data set. if you like, change it
# and see what happens...
codehash = Hash("code", data, 47)
print "--- Writing", FILE, "..."
fp = open(FILE, "w")
print >>fp, "/* this file was generated by %s %s */" % (SCRIPT, VERSION)
print >>fp
print >>fp, "#define NAME_MAXLEN", 256
print >>fp
print >>fp, "/* lexicon */"
Array("lexicon", lexicon).dump(fp, trace)
Array("lexicon_offset", lexicon_offset).dump(fp, trace)
# split decomposition index table
offset1, offset2, shift = splitbins(phrasebook_offset, trace)
print >>fp, "/* code->name phrasebook */"
print >>fp, "#define phrasebook_shift", shift
print >>fp, "#define phrasebook_short", short
Array("phrasebook", phrasebook).dump(fp, trace)
Array("phrasebook_offset1", offset1).dump(fp, trace)
Array("phrasebook_offset2", offset2).dump(fp, trace)
print >>fp, "/* name->code dictionary */"
codehash.dump(fp, trace)
fp.close()
# --------------------------------------------------------------------
# the following support code is taken from the unidb utilities
# Copyright (c) 1999-2000 by Secret Labs AB
# load a unicode-data file from disk
import sys
class UnicodeData:
def __init__(self, filename, exclusions, eastasianwidth, expand=1):
file = open(filename)
table = [None] * 0x110000
while 1:
s = file.readline()
if not s:
break
s = s.strip().split(";")
char = int(s[0], 16)
table[char] = s
# expand first-last ranges
if expand:
field = None
for i in range(0, 0x110000):
s = table[i]
if s:
if s[1][-6:] == "First>":
s[1] = ""
field = s[:]
elif s[1][-5:] == "Last>":
s[1] = ""
field = None
elif field:
field[0] = hex(i)
table[i] = field
# public attributes
self.filename = filename
self.table = table
self.chars = range(0x110000) # unicode 3.2
file = open(exclusions)
self.exclusions = {}
for s in file:
s = s.strip()
if not s:
continue
if s[0] == '#':
continue
char = int(s.split()[0],16)
self.exclusions[char] = 1
widths = [None] * 0x110000
for s in open(eastasianwidth):
s = s.strip()
if not s:
continue
if s[0] == '#':
continue
s = s.split()[0].split(';')
if '..' in s[0]:
first, last = [int(c, 16) for c in s[0].split('..')]
chars = range(first, last+1)
else:
chars = [int(s[0], 16)]
for char in chars:
widths[char] = s[1]
for i in range(0, 0x110000):
if table[i] is not None:
table[i].append(widths[i])
def uselatin1(self):
# restrict character range to ISO Latin 1
self.chars = range(256)
# hash table tools
# this is a straight-forward reimplementation of Python's built-in
# dictionary type, using a static data structure, and a custom string
# hash algorithm.
def myhash(s, magic):
h = 0
for c in map(ord, s.upper()):
h = (h * magic) + c
ix = h & 0xff000000L
if ix:
h = (h ^ ((ix>>24) & 0xff)) & 0x00ffffff
return h
SIZES = [
(4,3), (8,3), (16,3), (32,5), (64,3), (128,3), (256,29), (512,17),
(1024,9), (2048,5), (4096,83), (8192,27), (16384,43), (32768,3),
(65536,45), (131072,9), (262144,39), (524288,39), (1048576,9),
(2097152,5), (4194304,3), (8388608,33), (16777216,27)
]
class Hash:
def __init__(self, name, data, magic):
# turn a (key, value) list into a static hash table structure
# determine table size
for size, poly in SIZES:
if size > len(data):
poly = size + poly
break
else:
raise AssertionError, "ran out of polynominals"
print size, "slots in hash table"
table = [None] * size
mask = size-1
n = 0
hash = myhash
# initialize hash table
for key, value in data:
h = hash(key, magic)
i = (~h) & mask
v = table[i]
if v is None:
table[i] = value
continue
incr = (h ^ (h >> 3)) & mask;
if not incr:
incr = mask
while 1:
n = n + 1
i = (i + incr) & mask
v = table[i]
if v is None:
table[i] = value
break
incr = incr << 1
if incr > mask:
incr = incr ^ poly
print n, "collisions"
self.collisions = n
for i in range(len(table)):
if table[i] is None:
table[i] = 0
self.data = Array(name + "_hash", table)
self.magic = magic
self.name = name
self.size = size
self.poly = poly
def dump(self, file, trace):
# write data to file, as a C array
self.data.dump(file, trace)
file.write("#define %s_magic %d\n" % (self.name, self.magic))
file.write("#define %s_size %d\n" % (self.name, self.size))
file.write("#define %s_poly %d\n" % (self.name, self.poly))
# stuff to deal with arrays of unsigned integers
class Array:
def __init__(self, name, data):
self.name = name
self.data = data
def dump(self, file, trace=0):
# write data to file, as a C array
size = getsize(self.data)
if trace:
print >>sys.stderr, self.name+":", size*len(self.data), "bytes"
file.write("static ")
if size == 1:
file.write("unsigned char")
elif size == 2:
file.write("unsigned short")
else:
file.write("unsigned int")
file.write(" " + self.name + "[] = {\n")
if self.data:
s = " "
for item in self.data:
i = str(item) + ", "
if len(s) + len(i) > 78:
file.write(s + "\n")
s = " " + i
else:
s = s + i
if s.strip():
file.write(s + "\n")
file.write("};\n\n")
def getsize(data):
# return smallest possible integer size for the given array
maxdata = max(data)
if maxdata < 256:
return 1
elif maxdata < 65536:
return 2
else:
return 4
def splitbins(t, trace=0):
"""t, trace=0 -> (t1, t2, shift). Split a table to save space.
t is a sequence of ints. This function can be useful to save space if
many of the ints are the same. t1 and t2 are lists of ints, and shift
is an int, chosen to minimize the combined size of t1 and t2 (in C
code), and where for each i in range(len(t)),
t[i] == t2[(t1[i >> shift] << shift) + (i & mask)]
where mask is a bitmask isolating the last "shift" bits.
If optional arg trace is non-zero (default zero), progress info
is printed to sys.stderr. The higher the value, the more info
you'll get.
"""
import sys
if trace:
def dump(t1, t2, shift, bytes):
print >>sys.stderr, "%d+%d bins at shift %d; %d bytes" % (
len(t1), len(t2), shift, bytes)
print >>sys.stderr, "Size of original table:", len(t)*getsize(t), \
"bytes"
n = len(t)-1 # last valid index
maxshift = 0 # the most we can shift n and still have something left
if n > 0:
while n >> 1:
n >>= 1
maxshift += 1
del n
bytes = sys.maxint # smallest total size so far
t = tuple(t) # so slices can be dict keys
for shift in range(maxshift + 1):
t1 = []
t2 = []
size = 2**shift
bincache = {}
for i in range(0, len(t), size):
bin = t[i:i+size]
index = bincache.get(bin)
if index is None:
index = len(t2)
bincache[bin] = index
t2.extend(bin)
t1.append(index >> shift)
# determine memory size
b = len(t1)*getsize(t1) + len(t2)*getsize(t2)
if trace > 1:
dump(t1, t2, shift, b)
if b < bytes:
best = t1, t2, shift
bytes = b
t1, t2, shift = best
if trace:
print >>sys.stderr, "Best:",
dump(t1, t2, shift, bytes)
if __debug__:
# exhaustively verify that the decomposition is correct
mask = ~((~0) << shift) # i.e., low-bit mask of shift bits
for i in xrange(len(t)):
assert t[i] == t2[(t1[i >> shift] << shift) + (i & mask)]
return best
if __name__ == "__main__":
maketables(1)
|