[Aimmath-developers] Sorry ... new bug in LaTeX translation

[Greg G. <gr...@ma...>]

On Sat, 13 Sep 2003, Gustav W Delius wrote:
> 9 hours to go before the release of AiM 3.0!

Sorry but there still seem to be problems with the new LaTeX routines.

So far, I've been finding Maple 7 and Maple 8 perform similarly with
the latest development version of AiM (well they do now ... I noticed
that: sort(..., `<` @ evalf) works fine with Maple 8 to sort real numbers
that might include 3, 3.1, Pi etc., but I needed an extra evalb, i.e.
sort(..., evalb @ `<` @ evalf) to make it work with Maple 7).

However, some tricks (which I probably don't need to use anymore because
of the existence now of Ken's Inert package) don't work anymore:

Here are two examples:

nm> Symboltest1
l> x
h> x := -1;
t> $u @`` + x@$
a> 1
end>
nm> Symboltest2
l> x, xs
h> x := -1;
   xs := ``||x;
t> $@xs + 1@$
a> 1
end>

To explain, $u + @x@$ would give: u + -1
The Maple expression: `` + x 
sums the empty symbol (which is invisible) and x,
if x is positive, say x = 1, that gives: + 1
if x is -1 as above, it gives:           - 1
So, in particular, $u @`` + x@$ after Maple and tth one
should get (and used to):  u - 1         (when x = -1)
and:                       u + 1         (when x = 1)

This was a useful technique for adding a term into an expression
and getting the sign right without the + - juxtaposition, in cases
where one needed to avoid the use of $@u + x@$ for some reason.

At the moment, the first example is throwing up a Maple to LaTeX error.

The second example uses a feature of Maple to generate the symbol -1
(as opposed to the integer). By having x = -1, ``||x gives what looks
exactly like -1 but it's actually a symbol, i.e. a name that does not
get simplified. So, $@xs + 1@$ used to give: -1 + 1
... now it gives: `-1` + 1

I'm guessing that either the change is due to a missing eval somewhere
or changes made to the `aim/LaTeX` routines to make the Inert package
work. Is it possible, to have the old behaviour without breaking Inert?

  Regards,
  Greg