Google Charts, MathTran and editable PNG files Monday, Jan 14 2008
This post is about putting charts and formulas in your web pages, creating editable and scalable PNG files, and the need for a standard for embedded application data in image files.
Earlier today I looked at Google Charts, which allows you to ‘dynamically generate charts’. Send a Google a suitable GET request and you will get a pie chart, a bar chart or whatever, as specified in your query string. Their example is
which will produce the chart
This is rather similar to MathTran, where are URL such as
produces the image
Google Charts allows you to dynamically create graphs, and MathTran allows you to dynamically create rendered mathematical formulas. The Google API is rather better than MathTran’s, and it is certainly better documents. But MathTran has something that Google Charts doesn’t have … yet. The PNG’s returned by MathTran can be edited.
Happy birthday, Don Knuth! Sunday, Jan 13 2008
Earlier this week Don Knuth turned 70. This posting, inspired by a coordinated series of posts by admirers in mathematics and computer scientists, is my own personal statement of appreciation of his work. Mostly, I’ve been influenced by TeX, which Don Knuth wrote both as a labour of love, and as a means to the end of writing his multi-volume work The Art of Computer Programming (which is also a labour of love).
My first real contact with TeX was in 1987, five years after the first release of what has become the current version of TeX. Now the version number of TeX is, famously, converging to pi, but then it was something like 2.1. Previously I had written my PhD thesis out by hand, and skilled technical typists typed it up page by page, using the admirable IBM golfball typewriters. To obtain a special symbol, the typists had to manually change the golf-ball sized typehead. In 1986/7 I wrote a mathematics paper user the eqn preprocessor and the troff typesetting system that came with Unix. I was able to do this only because I had a lot of help from a technical typist who had several years experience with troff.