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828

answers:

2

Is there a way to get the Unicode Block of a character in python? The unicodedata module doesn't seem to have what I need, and I couldn't find an external library for it.

Basically, I need the same functionality as Character.UnicodeBlock.of() in java.

+4  A: 

I couldn't find one either. Strange!

Luckily, the number of Unicode blocks is quite manageably small.

This implementation accepts a one-character Unicode string, just like the functions in unicodedata. If your inputs are mostly ASCII, this linear search might even be faster than binary search using bisect or whatever. If I were submitting this for inclusion in the Python standard library, I'd probably write it as a binary search through an array of statically-initialized structs in C.

def block(ch):
  '''
  Return the Unicode block name for ch, or None if ch has no block.

  >>> block(u'a')
  'Basic Latin'
  >>> block(unichr(0x0b80))
  'Tamil'
  >>> block(unichr(0xe0080))

  '''

  assert isinstance(ch, unicode) and len(ch) == 1, repr(ch)
  cp = ord(ch)
  for start, end, name in _blocks:
    if start <= cp <= end:
      return name

def _initBlocks(text):
  global _blocks
  _blocks = []
  import re
  pattern = re.compile(r'([0-9A-F]+)\.\.([0-9A-F]+);\ (\S.*\S)')
  for line in text.splitlines():
    m = pattern.match(line)
    if m:
      start, end, name = m.groups()
      _blocks.append((int(start, 16), int(end, 16), name))

# retrieved from http://unicode.org/Public/UNIDATA/Blocks.txt
_initBlocks('''
# Blocks-5.1.0.txt
# Date: 2008-03-20, 17:41:00 PDT [KW]
#
# Unicode Character Database
# Copyright (c) 1991-2008 Unicode, Inc.
# For terms of use, see http://www.unicode.org/terms_of_use.html
# For documentation, see UCD.html
#
# Note:   The casing of block names is not normative.
#         For example, "Basic Latin" and "BASIC LATIN" are equivalent.
#
# Format:
# Start Code..End Code; Block Name

# ================================================

# Note:   When comparing block names, casing, whitespace, hyphens,
#         and underbars are ignored.
#         For example, "Latin Extended-A" and "latin extended a" are equivalent.
#         For more information on the comparison of property values, 
#            see UCD.html.
#
#  All code points not explicitly listed for Block
#  have the value No_Block.

# Property: Block
#
# @missing: 0000..10FFFF; No_Block

0000..007F; Basic Latin
0080..00FF; Latin-1 Supplement
0100..017F; Latin Extended-A
0180..024F; Latin Extended-B
0250..02AF; IPA Extensions
02B0..02FF; Spacing Modifier Letters
0300..036F; Combining Diacritical Marks
0370..03FF; Greek and Coptic
0400..04FF; Cyrillic
0500..052F; Cyrillic Supplement
0530..058F; Armenian
0590..05FF; Hebrew
0600..06FF; Arabic
0700..074F; Syriac
0750..077F; Arabic Supplement
0780..07BF; Thaana
07C0..07FF; NKo
0900..097F; Devanagari
0980..09FF; Bengali
0A00..0A7F; Gurmukhi
0A80..0AFF; Gujarati
0B00..0B7F; Oriya
0B80..0BFF; Tamil
0C00..0C7F; Telugu
0C80..0CFF; Kannada
0D00..0D7F; Malayalam
0D80..0DFF; Sinhala
0E00..0E7F; Thai
0E80..0EFF; Lao
0F00..0FFF; Tibetan
1000..109F; Myanmar
10A0..10FF; Georgian
1100..11FF; Hangul Jamo
1200..137F; Ethiopic
1380..139F; Ethiopic Supplement
13A0..13FF; Cherokee
1400..167F; Unified Canadian Aboriginal Syllabics
1680..169F; Ogham
16A0..16FF; Runic
1700..171F; Tagalog
1720..173F; Hanunoo
1740..175F; Buhid
1760..177F; Tagbanwa
1780..17FF; Khmer
1800..18AF; Mongolian
1900..194F; Limbu
1950..197F; Tai Le
1980..19DF; New Tai Lue
19E0..19FF; Khmer Symbols
1A00..1A1F; Buginese
1B00..1B7F; Balinese
1B80..1BBF; Sundanese
1C00..1C4F; Lepcha
1C50..1C7F; Ol Chiki
1D00..1D7F; Phonetic Extensions
1D80..1DBF; Phonetic Extensions Supplement
1DC0..1DFF; Combining Diacritical Marks Supplement
1E00..1EFF; Latin Extended Additional
1F00..1FFF; Greek Extended
2000..206F; General Punctuation
2070..209F; Superscripts and Subscripts
20A0..20CF; Currency Symbols
20D0..20FF; Combining Diacritical Marks for Symbols
2100..214F; Letterlike Symbols
2150..218F; Number Forms
2190..21FF; Arrows
2200..22FF; Mathematical Operators
2300..23FF; Miscellaneous Technical
2400..243F; Control Pictures
2440..245F; Optical Character Recognition
2460..24FF; Enclosed Alphanumerics
2500..257F; Box Drawing
2580..259F; Block Elements
25A0..25FF; Geometric Shapes
2600..26FF; Miscellaneous Symbols
2700..27BF; Dingbats
27C0..27EF; Miscellaneous Mathematical Symbols-A
27F0..27FF; Supplemental Arrows-A
2800..28FF; Braille Patterns
2900..297F; Supplemental Arrows-B
2980..29FF; Miscellaneous Mathematical Symbols-B
2A00..2AFF; Supplemental Mathematical Operators
2B00..2BFF; Miscellaneous Symbols and Arrows
2C00..2C5F; Glagolitic
2C60..2C7F; Latin Extended-C
2C80..2CFF; Coptic
2D00..2D2F; Georgian Supplement
2D30..2D7F; Tifinagh
2D80..2DDF; Ethiopic Extended
2DE0..2DFF; Cyrillic Extended-A
2E00..2E7F; Supplemental Punctuation
2E80..2EFF; CJK Radicals Supplement
2F00..2FDF; Kangxi Radicals
2FF0..2FFF; Ideographic Description Characters
3000..303F; CJK Symbols and Punctuation
3040..309F; Hiragana
30A0..30FF; Katakana
3100..312F; Bopomofo
3130..318F; Hangul Compatibility Jamo
3190..319F; Kanbun
31A0..31BF; Bopomofo Extended
31C0..31EF; CJK Strokes
31F0..31FF; Katakana Phonetic Extensions
3200..32FF; Enclosed CJK Letters and Months
3300..33FF; CJK Compatibility
3400..4DBF; CJK Unified Ideographs Extension A
4DC0..4DFF; Yijing Hexagram Symbols
4E00..9FFF; CJK Unified Ideographs
A000..A48F; Yi Syllables
A490..A4CF; Yi Radicals
A500..A63F; Vai
A640..A69F; Cyrillic Extended-B
A700..A71F; Modifier Tone Letters
A720..A7FF; Latin Extended-D
A800..A82F; Syloti Nagri
A840..A87F; Phags-pa
A880..A8DF; Saurashtra
A900..A92F; Kayah Li
A930..A95F; Rejang
AA00..AA5F; Cham
AC00..D7AF; Hangul Syllables
D800..DB7F; High Surrogates
DB80..DBFF; High Private Use Surrogates
DC00..DFFF; Low Surrogates
E000..F8FF; Private Use Area
F900..FAFF; CJK Compatibility Ideographs
FB00..FB4F; Alphabetic Presentation Forms
FB50..FDFF; Arabic Presentation Forms-A
FE00..FE0F; Variation Selectors
FE10..FE1F; Vertical Forms
FE20..FE2F; Combining Half Marks
FE30..FE4F; CJK Compatibility Forms
FE50..FE6F; Small Form Variants
FE70..FEFF; Arabic Presentation Forms-B
FF00..FFEF; Halfwidth and Fullwidth Forms
FFF0..FFFF; Specials
10000..1007F; Linear B Syllabary
10080..100FF; Linear B Ideograms
10100..1013F; Aegean Numbers
10140..1018F; Ancient Greek Numbers
10190..101CF; Ancient Symbols
101D0..101FF; Phaistos Disc
10280..1029F; Lycian
102A0..102DF; Carian
10300..1032F; Old Italic
10330..1034F; Gothic
10380..1039F; Ugaritic
103A0..103DF; Old Persian
10400..1044F; Deseret
10450..1047F; Shavian
10480..104AF; Osmanya
10800..1083F; Cypriot Syllabary
10900..1091F; Phoenician
10920..1093F; Lydian
10A00..10A5F; Kharoshthi
12000..123FF; Cuneiform
12400..1247F; Cuneiform Numbers and Punctuation
1D000..1D0FF; Byzantine Musical Symbols
1D100..1D1FF; Musical Symbols
1D200..1D24F; Ancient Greek Musical Notation
1D300..1D35F; Tai Xuan Jing Symbols
1D360..1D37F; Counting Rod Numerals
1D400..1D7FF; Mathematical Alphanumeric Symbols
1F000..1F02F; Mahjong Tiles
1F030..1F09F; Domino Tiles
20000..2A6DF; CJK Unified Ideographs Extension B
2F800..2FA1F; CJK Compatibility Ideographs Supplement
E0000..E007F; Tags
E0100..E01EF; Variation Selectors Supplement
F0000..FFFFF; Supplementary Private Use Area-A
100000..10FFFF; Supplementary Private Use Area-B

# EOF
''')
zaphod
A: 

unicodedata.name(chr)

That just returns the name of the character, not the block to which it belongs.
itsadok