[reportlab-users] Re: Plotting with logarithmic axes

[Berthold Höllmann]

Dinu Gherman <gherman@darwin.in-berlin.de> writes:

> Robin Becker:
>
>> Dinu and Andy originally decided against arguments for some reason, but
>> Andy has now come round to the opposite view and has made a sort of
>> giant factory function (at least for simple excel like charts).
>
> Ok, I claim, I'm also changing opinions when things can be improved.
> ;-) (I just thought about implementing a special variety of RL-bar-
> charts and got really mad about it... so I sort of needed the follow-
> ing little distraction.)
>
> A short verification shows that Mathematica also has half a dozen or
> more *Log*Plot() functions. That's ok as an abbreviation for inter-
> active use, but as a general API I don't really like it.
>
> Looking at Gnuplot, which can also be very interactive, you'll find
> the commands "set/unset logscale" which I find more useful in this
> context.

I do know gnuplot. I got the idea for my minor tics from gnuplot. The
predecessor of the programm I'm currently writing uses gnuplot and
LaTeX for the report generation.

> If you play a little bit with it you can quickly write a ReportLab-
> Graphics wrapper like I did to produce diagrams like these (making
> also use of my svglib module):
>
>    http://python.net/~gherman/tmp/lin_exp_x.pdf
>    http://python.net/~gherman/tmp/log_exp_x.pdf
>
> Gnuplot also writes PDF directly (using pdflib), but if you write
> your own wrapper you can reuse Gnuplot charts in your own RL docs,
> possibly really complicated ones like many on this page:
>
>    http://warmada.pandu.org/Graphics/gallery

I thought about gnuplot myself, but my boss dislikes the idea of
relying on an extenal program. If we decide to deliver our program to
collegues or to customers we would have to deliver gnuplot together
with a lot of Python modules. And the license of pdflib is quite
restictive. I would prefer to stay in Python.

Regards
Berthold
-- 
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