Re: [Groff] automatic equation numbering

[Anton Shterenlikht]

>From address@hidden Sun Mar 16 01:01:31 2014
>
>Here is a suggestion (it's a technique I use systematically for
>the purpose you describe). The following is in the context of ms
>macros, though the same (or possibly a slight variant) should work
>for other macro sets.
>
>**I first define an equation numbering and description system:
>
>.nr EQno 0 1
>.ds EQnxt \Z'\h'0.5m'[\\n+[EQno]\\$1]'
>.ds EQnow \Z'\h'0.5m'[\\n[EQno]\\$1]'
>.ds EQthing \Z'\h'0.5m'[\\$1]'
>
>These define an auto-incrementing equation number \n[EQno],
>so that, for instance (wsaqy we have already got up to equation [4],
>
>.EQ \*[EQnxt]
>phi ( x ) ~=~ exp( - half x sup 2 ) / sqrt{2 pi}
>.EN
>.ds EQnormdist \*[EQnow]
>
>Then the above equation will have its equation number (5) displayed
>to the right as " [5]", since the "\n+[EQno]" when "\n[EQnxt]" is
>read will first increment \n[EQno] from 4 to 5.

I cannot check with a graphical output right now,
but rendered with ascii, I get strange results:

$ cat bend.1
.nr EQno 0 1
.ds EQnxt \Z'\h'0.5m'(\\n+[EQno]\\$1)'
.ds EQnow \Z'\h'0.5m'(\\n[EQno]\\$1)'
.ds EQthing \Z'\h'0.5m'[\\$1]'
.NH 1
Some section
.PP
Eqn. \*[mumu] shows that ...
.EQ \*[EQnxt]
phi ( x ) ~=~ exp( - half x sup 2 ) / sqrt{2 pi}
.EN
.ds mumu \*[EQnow]
.ds mumua \*[EQnow a]
.ds mumub \*[EQnow b]
.PP
Eqns. \*[mumua], \*[mumub] ...
$ /usr/local/bin/groff -e -ms -Tascii bend.1 | head -n 15
bend.1:62: warning: can't find special character `*p'
bend.1:69: warning: can't find special character `sqrt'
bend.1:98: warning: can't find special character `sqrtex'
bend.1:107: warning: can't find special character `*f'






1.  Some section

     Eqn.  shows that ...

                       (x)=exp(-_x2)/2                      (1)


     Eqns. ,1(...

$

The last line of output is wrong.
It should've read "Eqns. (1a), (1b) ...".
What am I missing?

Also, how exactly do I run groff twice
to resolve the first, forward-looking reference?
Should I take care myself that some cross-referencing
information is saved to files?
Or is this done automatically with some
command line options with ms?

Many thanks

Anton