Bill Allombert on Sun, 24 Jan 2016 14:13:04 +0100

 Re: gp-inline tests in a document

On Sun, Jan 24, 2016 at 04:33:15PM +1100, Kevin Ryde wrote:
> In the unending battle against errors, I've been using gp to check
> formulas and sample values in TeX and elsewhere by writing test
> expressions as comments like "% GP-Test 2+2==4".  A gp-inline script
> (Perl) extracts and executes.
>
>     http://user42.tuxfamily.org/pari-gp-inline/index.html
>
> Tests in with the text help give some confidence to a claimed formula
> etc, especially if returning to the text later and being tempted to
> rearrange :-).
>
> There's a couple of lines of elisp for passing the expressions to
> pariemacs gp subprocess.  That can be any comment too so handy for gp
> one-liners as experiments etc elsewhere, eg. in program code.

For what is worth, I often do
\catcode*=13
\def*{\*}

in LaTeX document.  This allow TeX to understand polynomial expression
in GP format directly, so you can do
$$D = B^2 - 4*A*C$$
This reduce the risk of copy error.
Conversely I use a script to extract equations from the LaTeX file to
check them with GP.

Cheers,
Bill.

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