Hi
I think the error comes from your way of using \define: you use
\define\abs[1]{\lvert #1 \rvert}
instead of
\define[1]\abs{\lvert#1\rvert}
the following works fine for me:
\starttext
%\define[1]\abs{|#1|} % this works
\define[1]\abs{\lvert#1\rvert} % this works too
$\abs{-1} = 1$
\stoptext
Best regards: OK
On 4 juin 2011, at 22:40, Paul Menzel wrote:
> Dear ConTeXt folks,
>
>
> I want to define `\abs` as the command for the absolute value. The
> following minimal example is also attached.
>
> \define\abs[1]{\lvert #1 \rvert}
> \starttext
> $\lvert 2 \rvert$
>
> $\abs{2}$
> \stoptext
>
> This does not work though.
>
> $ context abs
> […]
> This is LuaTeX, Version beta-0.70.1-2011051923 (rev 4277)
> \write18 enabled.
> (abs.tex
>
> ConTeXt ver: 2011.05.18 22:26 MKIV fmt: 2011.5.27 int:
> english/english
> […]
> ! Missing $ inserted.
>
> system > tex > error on line 1 in file abs.tex: Missing $
> inserted ...
>
> 1 >> \define\abs[1]{\lvert #1 \rvert}
> 2 \starttext
> 3 $\lvert 2 \rvert$
> 4
> 5 $\abs{2}$
> 6 \stoptext
> 7
>
> <inserted text>
> $
> <to be read again>
> \Udelimiter
> \lvert ->\Udelimiter
> "4 "0 "7C
> l.1 \define\abs[1]{\lvert
> #1 \rvert}
> ?
>
> How should I do that correctly? I took that example from the user’s
> guide of the amsmath package (`texdoc amsldoc`).
>
>
> Thanks,
>
> Paul
> <abs.tex>___________________________________________________________________________________
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___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the
Wiki!
maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
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archive : http://foundry.supelec.fr/projects/contextrev/
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