- From: Oriol Boix <boix@ee.upc.es>
- Date: Mon, 15 Jan 2001 05:12:06 -0500 (EST)
- To: <www-math@w3.org>

Dear W3C friends, I am a Electrical Engineering professor in the Politechnical University of Catalonia (Spain) and the web-editor of our group. I am very interested in web accessibility and, so, the MathML interested me. In the MathML specification there are a lot of entity names but I think that it was convenient to add one. So this is a recomendation, no an errata. Electrical Engineering is one of the disciplines that uses complex numbers widely. But in Electrical Engineering we use the lowercase leters to indicate temporal functions. If I and U are current and voltage RMS values, i and u are current and voltage temporal functions (sinusoids in case of normal AC). In order to avoid confussion, we don't use the leter i to indicate imaginary components (and the square root of -1); in Electrical Engineering we use the letter j (For example: A+jB or 34+j9). If we are interested in write electrical expressions in MathML we must indicate the imaginary part with a variable named j or use the mathematical notation (with ⅈ or ⅈ) having the risk of misinterpretations in visual rendering users. I think that a good idea was to define an additional entity like &ImaginaryJ; or &ij;. Yours sincerely, Dr. Oriol Boix Aragonès Departament d'Enginyeria Elèctrica Universitat Politècnica de Catalunya P.S. Sorry, my English is not well.

Received on Tuesday, 16 January 2001 14:58:07 UTC