latex issues

[John H Palmieri]

There is some ugly LaTeX'ing going on in Sage:

In the notebook, try
{{{
%latex
$\sage{type(35))$
}}}
In this case, it uses the string "<type 'sage.rings.integer.Integer'>"
as text, but the < and > signs get converted into an upside-down
exclamation point and question mark.

Or click the "Typeset" button and try
{{{
type(35)
}}}
In this case, jsMath kicks in and tries to typeset "\text{<type
'sage.rings.integer.Integer'>}", but the symbols < and > confuse
jsMath -- it thinks they're part of an html command. As a result,
there is *no* output at all.

One more example, from a Sage doctest:
{{{
sage: R.<x,y>=QQbar[]
sage: latex(-x^2-y+1)
-x^{2} - y + \text{1}
}}}
What is that \text{1} doing there?

Here are my suggested solutions:

for problem 2, jsMath: use \hbox instead of \text. This seems to
work: {{{type(35)}}} prints out the correct string with the Typeset
button checked.

for problem 1, latex'ing type(...): use \texttt (typewriter font).
More precisely, when Sage can't figure out how to LaTeX something, it
converts it to a string and then encloses it in a \text{} command, and
I'm suggesting that we use \texttt{} instead. This is sort of like
verbatim output; in any case, it prints < and > correctly. It does
look different from \text, though. One example in the Sage code looks
like this:

sage: latex(CuspForms(3, 24).hecke_algebra()) # indirect doctest
\mathbf{T}_{\text{Cuspidal subspace of dimension 7 of Modular
Forms space of dimension 9 for Congruence Subgroup Gamma0(3) of weight
24 over Rational Field}}

With my proposed change, the subscript would appear in typewriter font
instead of plain text. I think the way to fix this is to modify the
_latex_ method for Hecke algebras. (I don't think it's going to look
very good with either \text or \texttt, in this example.)

for problem 3, -x^{2} - y + \text{1}: The issue is the same as problem
2: somehow, the element 1 has no _latex_ method, so Sage converts it
to a string and then encloses it in \text{}. I suggest this: if the
object has no conversion to latex, then as before, convert it to a
string. If the string contains only digits and/or letters, then just
use that string (so 'x' prints as an ordinary math-mode italic 'x',
not as an upright \text{x}, and '1' appears as '1': the above
situation would produce '-x^{2} - y + 1'). If the string contains
anything else -- "<", spaces, whatever -- then it gets printed using
\texttt{}, as explained above.

Comments?

John

[William Stein]

On Wed, Jul 8, 2009 at 11:35 AM, John H Palmieri<jhpalm...@gmail.com> wrote:
>
> There is some ugly LaTeX'ing going on in Sage:
>
> In the notebook, try
> {{{
> %latex
> $\sage{type(35))$
> }}}
> In this case, it uses the string "<type 'sage.rings.integer.Integer'>"
> as text, but the < and > signs get converted into an upside-down
> exclamation point and question mark.

Before reading further, when I see

$\sage{type(35))$

I immediately think *syntax error*, since you have an opening { but no
closing "}".

-- William

--
William Stein
Associate Professor of Mathematics
University of Washington
http://wstein.org

[John H Palmieri]

On Jul 8, 12:07 pm, William Stein <wst...@gmail.com> wrote:

> On Wed, Jul 8, 2009 at 11:35 AM, John H Palmieri<jhpalmier...@gmail.com> wrote:
>
> > There is some ugly LaTeX'ing going on in Sage:
>
> > In the notebook, try
> > {{{
> > %latex
> > $\sage{type(35))$
> > }}}
> > In this case, it uses the string "<type 'sage.rings.integer.Integer'>"
> > as text, but the < and > signs get converted into an upside-down
> > exclamation point and question mark.
>
> Before reading further, when I see
>
>  $\sage{type(35))$
>
> I immediately think *syntax error*, since you have an opening { but no
> closing "}".

Sorry, that's just a typo: I should have cut-and-pasted from my
worksheet. It should have been
{{{
%latex
$\sage{type(35)}$
}}}

John