Draw AVM

[James A. Crippen]

On Tue, 2 Jan 2001, Michael W. Daniels wrote:

> At 02:25 PM 1/2/01, James A. Crippen wrote:
> >So does anyone have some locations where LaTeX macros for HPSG could be
> >found?
>
> http://clwww.essex.ac.uk/latex4ling/
>
> is a good place to start.

Hey, just what I was looking for.

One note on a bug that I saw in the section on semantics.  Doug (or
Andrew?) says that "there is no built in command for the 'evaluation
function' eg [[_]]^{M,g}".  Not quite true.  I write lambda calculus a
frequently, and work with programming language semantics for functional
languages such as Scheme.  We use the same evaluation function (or
'interpretation') for the same purpose, to define the evaluation of a term
or expression in a certain model under an environment.  These brackets are
in the stmaryrd "St. Mary's Road" symbol font.  They are known as
\llbracket and \rrbracket after saying \usepackage[stmaryrd].  As a bonus,
these brackets are growing delimiters which work with \left and \right, so
you can use them around matrices, summations, fractions, etc.

This font/package has been included in most of the more recent (last
five years) TeX distributions that I've used on a number of systems.
It's also available from CTAN (http://ctan.tug.org).  It provides lots of
arrows, delimiters, operators, relations, and other goodies.

Here's an example semantics equation:

\begin{equation*}
 \llbracket (MN)\rrbracket^{\mathcal{M}} =
 (\llbracket M\rrbracket^{\mathcal{M}} \llbracket N\rrbracket^{\mathcal{M}})
\end{equation*}

but one could define the appropriate command

\begin{verbatim}
\newcommand{\evaluation}[2][]{\ensuremath{\llbracket #2\rrbracket^{#1}}}
\end{verbatim}

and then typing the above would be \textit{much} simpler:

\begin{equation*}
 \evaluation[\mathcal{M}]{(MN)} =
 (\evaluation[\mathcal{M}]{M} \evaluation[\mathcal{M}]{N})
\end{equation*}

Hope that helps!
'james

--
James A. Crippen <james at unlambda.com> ,-./-.  Anchorage, Alaska,
Lambda Unlimited: Recursion 'R' Us   |  |/  | USA, 61.2069 N, 149.766 W,
Y = \f.(\x.f(xx)) (\x.f(xx))         |  |\  | Earth, Sol System,
Y(F) = F(Y(F))                        \_,-_/  Milky Way.