From: David Carlisle <davidc@nag.co.uk>

Date: Fri, 31 Mar 2006 15:29:20 +0100

Message-Id: <200603311429.k2VETKv7029835@edinburgh.nag.co.uk>

To: juanrgonzaleza@canonicalscience.com

CC: www-math@w3.org

Date: Fri, 31 Mar 2006 15:29:20 +0100

Message-Id: <200603311429.k2VETKv7029835@edinburgh.nag.co.uk>

To: juanrgonzaleza@canonicalscience.com

CC: www-math@w3.org

> <apply><sqrt/>Content</apply> > > over something like > > <SQRT>content</SQRT> there are advantages when you look at extensions. <apply><csymbol>foobar</csymbol><cn>1</cn></apply> you know immediately that that is a foobar symbol applied to 1 and furthermore you do not need to extend the dtd to make that extension. If every function had a special content model then the dtd is a lot less flexible. (OpenMath takes a more extreme line than mathml here, some content mathml do use special forms, but the general design aims are the same. > I was not referring to the use of TeX syntax (which is not XML and > therefore omitted in MathML). I was referring to the fact that *base* is > outside of the “sup” tag in both SGML/HTML and TeX. That is, in TeX one > does not write things as the fact that TeX does not explictly mark the base of ^ expresions is a real problem when converting TeX to anything else. You have to parse back to find the base (and with TeX syntax that can never be more than a guess). superscript is almost always denoting a 2 argument function such as power(..,..), and it is far more natural to treat both those arguments in a consistent way, making them both children. > if you have something like > > <msup><mi>a</mi><mi>b</mi><mi>c</mi><mi>d</mi></msup> > > what mean "((ab)^c)d" or "a(b^c)d" or something else? Also MathML syntax > is ambiguous. This is reason that I carefully used an mrow example in my > previous post your example is a syntax error, so mathml would assign no meaning to it and it would be rejected by a mathml syste,. msup may only have two child elements and your example ha 4. > Are there technical/conceptual advantages introducing the base into the > script node or simply a matter of taste? Many advantages. It makes the function application clearer, and it makes it much easier to correctly position the superscrpt based on the size of the base. David ________________________________________________________________________ This e-mail has been scanned for all viruses by Star. The service is powered by MessageLabs. For more information on a proactive anti-virus service working around the clock, around the globe, visit: http://www.star.net.uk ________________________________________________________________________Received on Friday, 31 March 2006 14:31:33 UTC

*
This archive was generated by hypermail 2.3.1
: Tuesday, 6 January 2015 21:27:37 UTC
*