October 03, 2018

Digits int() doesn’t dig

Some time ago I wrote in More Than Just ASCII Digits about all the unicode characters Python’s int() function converts to numbers.

Recently I’ve discovered a discrepancy between those characters and the isdigit() method — there are characters where isdigit() returns True but int() does not convert them.

To make a list of those characters the program from the other blog entry was first ported to Python 3 and then changed to list all characters that are digits according to the isdigit() method, but raise a ValueError with int():

#!/usr/bin/env python3
import sys
import unicodedata


def main():
    for i in range(sys.maxunicode + 1):
        character = chr(i)
        try:
            int(character)
        except ValueError:
            if character.isdigit():
                name = unicodedata.name(character).lower()
                print(f'{character},{i:x},{name}')
        else:
            assert character.isdigit()


if __name__ == '__main__':
    main()

The assert in there isn’t triggered, which tells us all characters that can be converted actually have the „is digit“ property.

Here is the result:

All characters that are digits but can’t be converted by int().
Character Codepoint (hex) Name
² b2 superscript two
³ b3 superscript three
¹ b9 superscript one
፩ 1369 ethiopic digit one
፪ 136a ethiopic digit two
፫ 136b ethiopic digit three
፬ 136c ethiopic digit four
፭ 136d ethiopic digit five
፮ 136e ethiopic digit six
፯ 136f ethiopic digit seven
፰ 1370 ethiopic digit eight
፱ 1371 ethiopic digit nine
᧚ 19da new tai lue tham digit one
⁰ 2070 superscript zero
⁴ 2074 superscript four
⁵ 2075 superscript five
⁶ 2076 superscript six
⁷ 2077 superscript seven
⁸ 2078 superscript eight
⁹ 2079 superscript nine
₀ 2080 subscript zero
₁ 2081 subscript one
₂ 2082 subscript two
₃ 2083 subscript three
₄ 2084 subscript four
₅ 2085 subscript five
₆ 2086 subscript six
₇ 2087 subscript seven
₈ 2088 subscript eight
₉ 2089 subscript nine
① 2460 circled digit one
② 2461 circled digit two
③ 2462 circled digit three
④ 2463 circled digit four
⑤ 2464 circled digit five
⑥ 2465 circled digit six
⑦ 2466 circled digit seven
⑧ 2467 circled digit eight
⑨ 2468 circled digit nine
⑴ 2474 parenthesized digit one
⑵ 2475 parenthesized digit two
⑶ 2476 parenthesized digit three
⑷ 2477 parenthesized digit four
⑸ 2478 parenthesized digit five
⑹ 2479 parenthesized digit six
⑺ 247a parenthesized digit seven
⑻ 247b parenthesized digit eight
⑼ 247c parenthesized digit nine
⒈ 2488 digit one full stop
⒉ 2489 digit two full stop
⒊ 248a digit three full stop
⒋ 248b digit four full stop
⒌ 248c digit five full stop
⒍ 248d digit six full stop
⒎ 248e digit seven full stop
⒏ 248f digit eight full stop
⒐ 2490 digit nine full stop
⓪ 24ea circled digit zero
⓵ 24f5 double circled digit one
⓶ 24f6 double circled digit two
⓷ 24f7 double circled digit three
⓸ 24f8 double circled digit four
⓹ 24f9 double circled digit five
⓺ 24fa double circled digit six
⓻ 24fb double circled digit seven
⓼ 24fc double circled digit eight
⓽ 24fd double circled digit nine
⓿ 24ff negative circled digit zero
❶ 2776 dingbat negative circled digit one
❷ 2777 dingbat negative circled digit two
❸ 2778 dingbat negative circled digit three
❹ 2779 dingbat negative circled digit four
❺ 277a dingbat negative circled digit five
❻ 277b dingbat negative circled digit six
❼ 277c dingbat negative circled digit seven
❽ 277d dingbat negative circled digit eight
❾ 277e dingbat negative circled digit nine
➀ 2780 dingbat circled sans-serif digit one
➁ 2781 dingbat circled sans-serif digit two
➂ 2782 dingbat circled sans-serif digit three
➃ 2783 dingbat circled sans-serif digit four
➄ 2784 dingbat circled sans-serif digit five
➅ 2785 dingbat circled sans-serif digit six
➆ 2786 dingbat circled sans-serif digit seven
➇ 2787 dingbat circled sans-serif digit eight
➈ 2788 dingbat circled sans-serif digit nine
➊ 278a dingbat negative circled sans-serif digit one
➋ 278b dingbat negative circled sans-serif digit two
➌ 278c dingbat negative circled sans-serif digit three
➍ 278d dingbat negative circled sans-serif digit four
➎ 278e dingbat negative circled sans-serif digit five
➏ 278f dingbat negative circled sans-serif digit six
➐ 2790 dingbat negative circled sans-serif digit seven
➑ 2791 dingbat negative circled sans-serif digit eight
➒ 2792 dingbat negative circled sans-serif digit nine
𐩀 10a40 kharoshthi digit one
𐩁 10a41 kharoshthi digit two
𐩂 10a42 kharoshthi digit three
𐩃 10a43 kharoshthi digit four
𐹠 10e60 rumi digit one
𐹡 10e61 rumi digit two
𐹢 10e62 rumi digit three
𐹣 10e63 rumi digit four
𐹤 10e64 rumi digit five
𐹥 10e65 rumi digit six
𐹦 10e66 rumi digit seven
𐹧 10e67 rumi digit eight
𐹨 10e68 rumi digit nine
𑁒 11052 brahmi number one
𑁓 11053 brahmi number two
𑁔 11054 brahmi number three
𑁕 11055 brahmi number four
𑁖 11056 brahmi number five
𑁗 11057 brahmi number six
𑁘 11058 brahmi number seven
𑁙 11059 brahmi number eight
𑁚 1105a brahmi number nine
🄀 1f100 digit zero full stop
🄁 1f101 digit zero comma
🄂 1f102 digit one comma
🄃 1f103 digit two comma
🄄 1f104 digit three comma
🄅 1f105 digit four comma
🄆 1f106 digit five comma
🄇 1f107 digit six comma
🄈 1f108 digit seven comma
🄉 1f109 digit eight comma
🄊 1f10a digit nine comma
Posted by Marc 'BlackJack' Rintsch
Filed under: Python
Tags: python, unicode