4CornerIndex-to-Text

Translate the 4-corner indexes to Chinese text.

Motivation:

A few days ago, my friend SUN ZHIZHENG, who is a writer, shared a post on social media, where he mentioned the concept of creating a book titled 《 $\pi$ 》: use the 4-corner index method to encode the digits of $\pi$ into an endless sequence of Chinese characters, forming a book without a final page. The idea fascinated me and sparked my imagination. Inspired by this, I decided to try bringing it to life using Python here. (of course only to a certain extent :) ).

My Steps:

1. Extract the 4CornerIndex mapping file from the html file converted from the original source .chm file.

   • Text version with count: extracted_map.txt
   • Json version: 4CornerIndex_mapping.json

2. Generate large number of digits of the constant $\pi$.

   • $\pi$ of 1 million digits: pi1m.txt
   • $\pi$ of 50 million digits: pi50m.txt

3. Generate text with translating the digits of $\pi$ as 4-corner indexes to Chinese.

   • Text from $\pi$ of 1 million digits: text_from_pi_1M_digits.txt
   • Text from $\pi$ of 50 million digits: text_from_pi_50M_digits.txt

4. Render the text to pdf by using Tex. (IDE: TeXstudio ; Compiler: XeLaTex )

   • Pi Book of text from $\pi$ of 1 million digits: tex , pdf
   • Pi Book of text from $\pi$ of 50 million digits: tex , pdf

- PS: Naturally this can be extended to other irrational numbers like $e$, $\sqrt2$, golden ratio ($1+\sqrt5/2$) .

App:

I turned it into an app for translating input number as 4-corner indexes to Chinese:

• http://yuanhes.com/translate_4CI

(As I tried, the phone browsers cannot display most of the characters due to encoding issue, while the computer browsers perform much better.)

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References:

• 四角号码检字表（勘误版）.zip 来源：http://bbs.unispim.com/forum.php?mod=viewthread&tid=31674
• Pi digits source: https://www.angio.net/pi/digits.html

  "50 million digits (compressed, special): You can download 50 million from the Pi searcher here. These digits are packed together two per byte, so you'll have to download, compile, and use this program to print them. Geeks only, sorry."

• A program can be used for computing large number of digits of irrational constants: y-cruncher
• Wikipedia page for 4-corner method: Four-corner method - Wikipedia
• Method for handling the rendering issue of Chinese charactes of different fonts (character sets): xetex - Vertical Chinese text that contains characters in a "CJK fallback family font" - TeX - LaTeX Stack Exchange