Feedback to 4 June 2009 ED from Japan

3.2 Algorithmic

cjk-ideographic

The cjk-ideographic algorithm is used by several numbering systems, using different sets of digits. These systems are defined for numbers greater than or equal to 0 and less than 10¹⁶. Numbers less than zero or equal to or greater than 10¹⁶ should use the decimal system. The core algorithm is as follows:

1. Split the decimal number into groups of four digits, starting with the least significant digit.
2. Ignoring groups that have the value zero, append the second group marker to the second group, the third group marker to the third group, and the fourth group marker to the fourth group. These markers are defined in the tables for the specific numbering systems. The first group has no marker.
3. For each group, ignoring digits that have the value zero, append the second digit marker to the second digit, the third digit marker to the third digit, and the fourth digit marker to the fourth digit. These markers are defined in the tables for the specific numbering systems. The first digit has no marker.
4. For any group with a value less than 20, remove the second digit (the 1 in the tens column). Leave any associated markers.
5. Concatenate the groups back into a single string, least significant group last.
6. Collapse any consecutive runs of 0 digits to a single 0.
7. Replace each digit with the relevant character selected from the numbering system's table.

The suffix for the cjk-ideographic numbering systems is a dot (. U+002E FULL STOP). Is there a better suffix to use?

If specified explicitly, the cjk-ideograph keyword should be handled like either one of ''japanese-informal'', ''simp-chinese-informal'', or ''trad-chinese-informal''. The UA should use its own logic to determine which one to use.trad-chinese-informal.

japanese-formal

This uses the cjk-ideographic system with the following modifications to the rules and the following table.

• Do not apply the rule 4.
• In the rule 6, remove all 0 digits, not only consecutive runs of 0 digits. If nothing is left; i.e., if the original value before splitting into gruops is zero, use single digit 0.

Formal Japanese numbering system

Values	Codepoints
Second Group Marker	萬万	U+842C4E07
Third Group Marker	億	U+5104
Fourth Group Marker	兆	U+5146
Second Digit Marker	拾	U+62FE
Third Digit Marker	百佰	U+767E4F70
Fourth Digit Marker	阡仟	U+96214EDF
Digit 0	〇零	U+300796F6
Digit 1	壱壹	U+58F158F9
Digit 2	弐貳	U+5F108CB3
Digit 3	参參	U+53C23
Digit 4	四肆	U+56DB8086
Digit 5	伍	U+4F0D
Digit 6	六陆	U+516D9646
Digit 7	七柒	U+4E0367D2
Digit 8	八捌	U+516B634C
Digit 9	九玖	U+4E5D7396

While these codepoints are chosen based on 1) bank rules for writing checks, and 2) compatibility with ECMA-376 (OOXML), some argued that these codepoints should be modern-ized, like 万 for second group marker or 千 for fourth digit marker. It would be ideal if UA/users can create their own @counter-style by specifying the algorithm and codepoints for markers, digits, and minus sign.

The suffix is U+3001 (、), and minus sign is U+FF0D (－). or U+002D or ''▲'' or ''マイナス'' (a string of four characters).

1010010 is 壱佰壱萬壱拾.

japanese-informal

This uses the cjk-ideographic system with the following modifications to the rules and the following table.

• In the rule 3, if the digit is 1, the digit marker should be used without the digit 1.
• The rule 4 is not necessary because the above modification to the rule 3 covers it.
• In the rule 6, remove all 0 digits, not only consecutive runs of 0 digits. If nothing is left; i.e., if the original value before splitting into gruops is zero, use single digit 0.

Informal Japanese numbering system

Values	Codepoints
Second Group Marker	万萬	U+4E07842C
Third Group Marker	億	U+5104
Fourth Group Marker	兆	U+5146
Second Digit Marker	十萬	U+5341842C
Third Digit Marker	百億	U+767E5104
Fourth Digit Marker	千兆	U+53435146
Digit 0	〇零	U+300796F6
Digit 1	一壹	U+4E0058F9
Digit 2	二贰	U+4E8C8D30
Digit 3	三叁	U+4E0953C1
Digit 4	四肆	U+56DB8086
Digit 5	五伍	U+4E944F0D
Digit 6	六陆	U+516D9646
Digit 7	七柒	U+4E0367D2
Digit 8	八捌	U+516B634C
Digit 9	九玖	U+4E5D7396

The suffix is U+3001 (、), and minus sign is U+FF0D (－). or U+002D or ''▲'' or ''マイナス'' (a string of four characters).

1010010 is 百一万十.

3.3 Numeric

<numeric>

arabic-indic | binary | bengali | cambodian | decimal | decimal-leading-zero | devanagari | gujarati | gurmukhi | japanese | kannada | khmer | lao | lower-hexadecimal | malayalam | mongolian | myanmar | octal | oriya | persian | super-decimal | telugu | tibetan | thai | upper-hexadecimal | urdu

3.4 Alphabetic

3.6 Non-repeating