Xah Emacs Blog Archive 2010-10

Today, i need to study how Mathematica treats Unicode. [see How Mathematica does Unicode?]. In the process, i need to get a file of math Unicode symbols. I have a page at Math Symbols in Unicode, but i need just the Unicode symbols, not all other content.

So, simply copy the whole file content. Then, put that into a file, say math_symbols_unicode.txt. Then, delete all asccii chars. This you can do by calling “query-replace-regexp”. [see Emacs: Find Replace in Current File] For the replace regex, use [[:ascii:]]. For the replacement string, just press Enter for nothing. Then, press ! to replace all.

Now, i need a space between each symbol. This is a great job for Emacs keyboard macros. Type Ctrl+x ( to start recording. Then type → space. Then type Ctrl+x ) to end recording. Then, type Ctrl+u 999 (for repeating 999 times the next command), then Alt+x call-last-kbd-macro . Then, spaces are inserted between each chars.

Thanks to Lew Perin http://www.panix.com/~perin/ for a correction.

Aaron wrote to note that, to add a space between each char, it's simpler to actually do another query-replace-regexp. Use $.$ for the find regex, and use \1 for the replacement string.

How to force upcase of replacement?

In your replacement, use: \,(upcase \1). For detail, see: Emacs: Find Replace in Current File.

2010-10-16

Requesting guest blog writers for emacs. If you have used emacs for few years, and better if code emacs lisp, please just send your article to me (Xah@XahLee.org) and i'll post it, with links to your sites and all.

The article should be preferably technical than opinion piece or diary. For example, a short tutorial on installing and using a mode (blogging, twitter, hooking up with gmail, how to use planner, muse, intro to CEDET, etc.) It also can be some tips on commonly needed things, such as how to setup and use tags, etc.

If you are not familiar already, guest blogging has many advantages, as developed in the blogsphere community. It helps the community of the blog subject, gives readers a fresh writing style to read, saves the original blog author time, advertise for the guest author. It is practiced in the printed media for long. You can read about guest blogging here: Guest Blogging 101, from Darren Rowse.

I would like to try the guest blog idea. Give it a shot, why not?

If you haven't blogged before, here's some tips:

Let the article be self-contained and concrete, as much as possible. For example, instead of writing “read the instruction at xyz.com”, simply pull the code from your “.emacs” as a concrete example. Say “put the file abc in the dir ~/.emacs/d/”, instead of saying “put it in your lib path”.
Cover the most basic things about xyz that 90% of emacs users will need to do. Majority of emacs users are not emacs geeks and many don't know or read blogs, wiki, or reddit. (many simply web search for a problem they need to solve.)
Make it as simple as possible, or even write it as instructions or receipe. Make it into sections. Each section cover one thing. Each paragraph contains one idea.
When readers read the article, if they just spend 1 min they would have learned something. Don't make them think.
Don't worry about some academic correctness or formality or completeness. Readers are not dummies, they understand the context. They can read the doc for detail if they want to.

2010-10-14

Emacs: File Encoding

2010-10-09

Emacs: eshell

2010-10-05

Emacs thing-at-point and Chaining Functions

2010-10-05

ELisp: Cycle Space Hyphen Underscore (tutorial; useful command)

2010-10-01

Emacs Dev Inefficiency and Emacs Web 2.0? (2010) (rant)