mirror of https://github.com/texmacs/doc.git
92 lines
4.3 KiB
Plaintext
92 lines
4.3 KiB
Plaintext
|
<TeXmacs|1.0.7.9>
|
||
|
|
|
||
|
|
<style|tmdoc>
|
||
|
|
|
||
|
|
<\body>
|
||
|
|
<tmdoc-title|Customized mathematical semantics>
|
||
|
|
|
||
|
|
We have done our best to support most of the classical mathematical
|
||
|
|
notations. Nevertheless, the user may sometimes want to define notations
|
||
|
|
with a non standard semantics. Certain areas may also require special
|
||
|
|
notations which are not supported by default.
|
||
|
|
|
||
|
|
<TeXmacs> provides a very simple <markup|syntax> primitive, which allows
|
||
|
|
the user to manually override the default syntactical semantics of a
|
||
|
|
formula. Assuming that semantic editing was activated, you may insert the
|
||
|
|
<markup|syntax> primitive using <shortcut|(make 'syntax)> or
|
||
|
|
<menu|Insert|Semantics|Other>. The first argument contains the formula as
|
||
|
|
it should be displayed, whereas the second argument contains the formula as
|
||
|
|
it should be interpreted.
|
||
|
|
|
||
|
|
For instance, if we enter <math|\<cal-R\>> as the first argument and
|
||
|
|
<math|\<less\>> as the second one, then the <math|\<cal-R\>> will be
|
||
|
|
interpreted as a binary relation, exactly in the same way as
|
||
|
|
<math|\<less\>>. Moreover, the spacing around <math|\<cal-R\>> will be
|
||
|
|
adapted, so as to mimick the spacing around <math|\<less\>>. In this
|
||
|
|
particular example, we might have obtained the same result by using the
|
||
|
|
<markup|math-relation> primitive, which is equivalent to <markup|syntax>
|
||
|
|
with<nbsp><math|\<less\>> as its second argument. Most standard operator
|
||
|
|
types are available from <menu|Insert|Semantics>, or using the
|
||
|
|
<prefix|math:syntax> keyboard prefix. In particular, you may use
|
||
|
|
<shortcut|(make 'math-ignore)> to simply ignore a formula and
|
||
|
|
<shortcut|(make 'math-ordinary)> in order to make the formula behave as an
|
||
|
|
ordinary symbol (such as the letter ``o'').
|
||
|
|
|
||
|
|
The <markup|syntax> primitive is especially powerful when used in
|
||
|
|
combination with the <TeXmacs> macro language. For instance, consider the
|
||
|
|
formula <math|C=1/2*\<mathpi\>*\<mathi\>*<big-around|\<oint\>|f<around*|(|z|)>*\<mathd\>
|
||
|
|
z>>. It is likely that the inteded interpretation of
|
||
|
|
<math|1/2*\<mathpi\>*\<mathi\>> is <math|1/<around*|(|2*\<mathpi\>*\<mathi\>|)>>
|
||
|
|
and not <math|<around*|(|1/2|)>*\<mathpi\>*\<mathi\>>. Therefore, if we
|
||
|
|
often use the constant <math|2*\<mathpi\>*\<mathi\>>, then we might want to
|
||
|
|
define a macro<nbsp><markup|twopii> by
|
||
|
|
|
||
|
|
<\tm-fragment>
|
||
|
|
<inactive|<assign|twopii|<inactive|<macro|<inactive|<syntax|<math|2*\<pi\>*\<mathi\>>|<math|(2*\<pi\>*\<mathi\>)>>>>>>>
|
||
|
|
</tm-fragment>
|
||
|
|
|
||
|
|
Such macros may be grouped together into a style package with the user's
|
||
|
|
favourite notations. Future versions of <TeXmacs> might also provide style
|
||
|
|
packages with notations dedicated to specific<nbsp>areas.
|
||
|
|
|
||
|
|
Let us finally notice that there are usually several ways for redefining
|
||
|
|
the semantics of a formula. For instance, an alternative way to define the
|
||
|
|
macro <markup|twopii> is using
|
||
|
|
|
||
|
|
<\tm-fragment>
|
||
|
|
<inactive|<assign|twopii|<inactive|<macro|<math|<around*|\<nobracket\>|2*\<mathpi\>*\<mathi\>|\<nobracket\>>>>>>>
|
||
|
|
</tm-fragment>
|
||
|
|
|
||
|
|
where we inserted a pair of invisible brackets around
|
||
|
|
<math|2*\<mathpi\>*\<mathi\>>. Similarly, in the formula
|
||
|
|
|
||
|
|
<\equation*>
|
||
|
|
\<mathe\><rsup|<sqrt|x>+\<mathe\><rsup|<sqrt|log
|
||
|
|
x>+\<mathe\><rsup|<sqrt|log log x>+<math-ordinary|\<udots\>\<ddots\>>+log
|
||
|
|
log log x>+log log x>+log x>,
|
||
|
|
</equation*>
|
||
|
|
|
||
|
|
we may either select the whole formula and give it the semantics of an
|
||
|
|
ordinary symbol, by pressing<nbsp><shortcut|(make 'math-ordinary)>.
|
||
|
|
However, a nicer solution is to only select the subformula
|
||
|
|
<math|<math-ordinary|\<udots\>\<ddots\>>>, and give it the semantics of an
|
||
|
|
ordinary symbol. Yet another example is the sign sequence <math|++-+-+>
|
||
|
|
mentioned earlier. This sequence can be interpreted correctly by inserting
|
||
|
|
invisible separators between the different signs using the <key|, space>
|
||
|
|
shortcut.
|
||
|
|
|
||
|
|
<tmdoc-copyright|2011|Joris van der Hoeven>
|
||
|
|
|
||
|
|
<tmdoc-license|Permission is granted to copy, distribute and/or modify this
|
||
|
|
document under the terms of the GNU Free Documentation License, Version 1.1
|
||
|
|
or any later version published by the Free Software Foundation; with no
|
||
|
|
Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
|
||
|
|
Texts. A copy of the license is included in the section entitled "GNU Free
|
||
|
|
Documentation License".>
|
||
|
|
</body>
|
||
|
|
|
||
|
|
<\initial>
|
||
|
|
<\collection>
|
||
|
|
<associate|language|english>
|
||
|
|
</collection>
|
||
|
|
</initial>
|