view: change engine default value from 'latex' to 'pdflatex'

[slabbe]

In view function, the default value for engine argument is 'latex'. With this value, the compilation is trying (tex -> dvi -> png, and if an exception raised then dvi -> ps -> pdf). For some input, it is broken (example below) because of overfull vbox and overfull hbox created in the first tex -> dvi compilation.

When engine is 'pdflatex', the compilation just work.

The purpose of this ticket is to change engine default value from 'latex' to 'pdflatex'.

EXAMPLE::

Create this graph:

sage: F = GF(3)
sage: gens = [matrix(F,2,[1,0, 1,1]), matrix(F,2, [1,1, 0,1])]
sage: group = MatrixGroup(gens)
sage: G = group.cayley_graph()

It is not too big:

sage: G
Digraph on 24 vertices

Note that since the vertices of G are matrices, the default format='tkz_graph' ​does not work. One need to use format='dot2tex'.

With dot2tex-2.8.7-2 and graphviz installed, the following work:

sage: G.set_latex_options(format='dot2tex', prog='neato')
sage: view(G)
sage: G.set_latex_options(format='dot2tex', prog='twopi')
sage: view(G)
sage: G.set_latex_options(format='dot2tex', prog='fdp')
sage: view(G)

But not these ones:

sage: G.set_latex_options(format='dot2tex', prog='dot')
sage: view(G)
An error occurred.
...
LaTex error
sage: G.set_latex_options(format='dot2tex', prog='circo')
sage: view(G)
An error occurred.
...
LaTex error

It turns out that the following works:

sage: G.set_latex_options(format='dot2tex', prog='dot')
sage: view(G, engine='pdflatex')
sage: G.set_latex_options(format='dot2tex', prog='circo')
sage: view(G, engine='pdflatex')

The following does the trick:

sage: view(G, engine='pdflatex', tightpage=True)

Apply trac_13713_engine_pdflatex-sl.patch​, trac_13713-examples-jhp.patch​.

[jhpalmieri]

If you run view(G, debug=True), you should get more information about the error.

[slabbe]

If you run view(G, debug=True), you should get more information about the error.

In a working example, relevant part of the log is below. So if I understand correctly, the command view is first trying the path tex -> dvi -> png, if some error occurs, then tries dvi -> ps -> pdf. And now I understand why it is so slow when it works::

sage: sage: G.set_latex_options(format='dot2tex', prog='neato')
sage: view(G, debug=True)
\documentclass{article}
...
\begin{document}
...
\end{document}
['sage-native-execute', 'latex', '\\nonstopmode', '\\input{sage.tex}']
['sage-native-execute', 'dvipng', '--picky', '-q', '-T', 'tight', '-D', '150', 'sage.dvi', '-o', 'sage.png']
This is pdfTeX, Version 3.1415926-1.40.10 (TeX Live 2009)
entering extended mode
LaTeX2e <2009/09/24>
Babel ...
...
Output written on sage.dvi (1 page, 32420 bytes).
Transcript written on sage.log.
This is dvipng 1.12 Copyright 2002-2008 Jan-Ake Larsson
GPL Ghostscript 8.70: Unrecoverable error, exit code 1
...
GPL Ghostscript 8.70: Unrecoverable error, exit code 1
bad dvi file; running dvips and ps2pdf instead...
['sage-native-execute', 'dvips', 'sage.dvi']
['sage-native-execute', 'ps2pdf', 'sage.ps']
This is dvips(k) 5.98 Copyright 2009 Radical Eye Software (www.radicaleye.com)
' TeX output 2012.11.16:0002' -> sage.ps
...
viewer: "sage-open"
sage: 

And, now the log of the non working example is below. There are some Overfull vbox and hbox during the latex -> dvi phase so that the next dvi -> png ends with an error and thus does not try "running dvips and ps2pdf instead..." as above :

sage: sage: G.set_latex_options(format='dot2tex', prog='dot')
sage: view(G, debug=True)
\documentclass{article}
...
\begin{document}
...
\end{document}
['sage-native-execute', 'latex', '\\nonstopmode', '\\input{sage.tex}']
['sage-native-execute', 'dvipng', '--picky', '-q', '-T', 'tight', '-D', '150', 'sage.dvi', '-o', 'sage.png']
This is pdfTeX, Version 3.1415926-1.40.10 (TeX Live 2009)
entering extended mode
LaTeX2e <2009/09/24>
Babel ...
...
Overfull \hbox (138.51622pt too wide) detected at line 119
[]
[1]
Overfull \vbox (677.07953pt too high) has occurred while \output is active [2] (./sage.aux) )
(see the transcript file for additional information)
Output written on sage.dvi (2 pages, 35212 bytes).
Transcript written on sage.log.
This is dvipng 1.12 Copyright 2002-2008 Jan-Ake Larsson
GPL Ghostscript 8.70: Unrecoverable error, exit code 1
...
GPL Ghostscript 8.70: Unrecoverable error, exit code 1
An error occurred.
This is pdfTeX, Version 3.1415926-1.40.10 (TeX Live 2009) (format=latex 2011.4.19)  15 NOV 2012 23:59
entering extended mode
...
...
...
...
...
Overfull \hbox (138.51622pt too wide) detected at line 119 [] []
[1] Overfull \vbox (677.07953pt too high) has occurred while \output is active []
...
...
Output written on sage.dvi (2 pages, 35212 bytes).

Latex error
sage: 

[slabbe]

Okay, it turns out that the default compilation (try : tex -> dvi -> png, except: dvi -> ps -> pdf) which doesn't like overfull vbox and hbox can be changed using the engine option. Thus,

sage: G.set_latex_options(format='dot2tex', prog='dot')
sage: view(G, engine='pdflatex')

and

sage: G.set_latex_options(format='dot2tex', prog='circo')
sage: view(G, engine='pdflatex')

both compile fine and give pdf files with clear overfull vbox and hbox. And, one can see the complete graphs by using tightpage=True:

sage: G.set_latex_options(format='dot2tex', prog='dot')
sage: view(G, engine='pdflatex', tightpage=True)
sage: G.set_latex_options(format='dot2tex', prog='circo')
sage: view(G, engine='pdflatex', tightpage=True)

[slabbe]

So before closing this ticket, I ask the following question:

Why is the default compilation of the command view doing (try : tex -> dvi -> png, except: dvi -> ps -> pdf) ? In which case is it better to do (tex -> dvi -> png) or (tex -> dvi -> ps -> pdf) rather then simply (tex -> pdf) ?

It has been a long time since I have seen pstricks code around here... and I would like

view(G)

to just work.

[nthiery]

At first sight, I am also in favor of switching to pdflatex as default engine.

[jhpalmieri]

Replying to nthiery:

At first sight, I am also in favor of switching to pdflatex as default engine.

Sounds okay to me.

[slabbe]

tested on sage-5.7.beta4

[jhpalmieri]

I'm happy with the main patch. I think it requires some modifications to the documentation in the latex_examples class, so I've attached a referee patch to deal with that.

[tscrim]

For what it's worth, I was getting the "latex error" on just using view with 'latex' after I did some updatings (even doing something as simple as view(2)). However with the 'pdflatex', things are working again, so I think this is a good switch to make.

[jdemeyer]

Don't forget to indicate which patch(es) need to be applied.

[slabbe]

There are 5 tests failing on the patchbot, but do not seem related to this ticket :

sage -t sage/interfaces/expect.py  # 1 doctest failed
sage -t sage/interacts/debugger.py  # 8 doctests failed
sage -t doc/en/prep/Intro-Tutorial.rst  # Killed due to kill signal
sage -t sage/modules/free_module_homspace.py  # Killed due to kill signal
sage -t sage/graphs/generators/world_map.py  # Killed due to kill signal

[tscrim]

Everything looks good to me.