matplotlib-devel Mailing List for matplotlib

On Monday 21 August 2006 13:56, Paulo Jose da Silva e Silva wrote:
> Hello,
>
> I am using numpy 1.0b2 + matplotlib 0.87.4 from Andrew Straw repository
> for Ubuntu (http://debs.astraw.com/).
>
> I am playing with some images to present the Theorem of Best
> Approximation associated to SVD to my students. I have computed a small
> approximated image and I want to plot it using imshow from matplotlib,
> but this command presenting a weird behavior with some weird spots in
> brigh regions.
>
> If I convert the array to a Numeric array and show it with the view
> command from NumTut package (the Numeric tutorial) the picture shows
> correctly.
>
> Did I find a bug?
I can confirm the strange behavior with the most up-to-date svn versions of 
matplotlib and numpy.

Thanks all for the tips,
Darren, that's exactly what I had in mind - mathtext should copy the
syntax of (La)TeX to a tollerable extent (without those dirty macros),
so at least the high level TeX constructs behave the same.
This should allow users to plot everyday plots easily with mathtext,
and when they want a publication ready EPS (perhaps one day mathtext
will be good enough for it), they'll just add the option usetex, with
no other code change.
I think it's easier to stick with plain TeX's syntax because it's very
well documented.
Cheers,
Edin
On 8/21/06, Darren Dale <dd...@co...> wrote:
> I think what he meant to say was that old mathtext didnt behave the way TeX
> does, is that correct Edin? My feeling is that mpl should replicate the
> (La)TeX syntax exactly. Imagine the confusion if mathtext gives one result,
> and usetex gives another.
>

Hello,
I am using numpy 1.0b2 + matplotlib 0.87.4 from Andrew Straw repository
for Ubuntu (http://debs.astraw.com/). 
I am playing with some images to present the Theorem of Best
Approximation associated to SVD to my students. I have computed a small
approximated image and I want to plot it using imshow from matplotlib,
but this command presenting a weird behavior with some weird spots in
brigh regions. 
If I convert the array to a Numeric array and show it with the view
command from NumTut package (the Numeric tutorial) the picture shows
correctly.
Did I find a bug?
To see what I mean, you can download the following small data file
(saved with "tofile" in a i386 systems, it may not work in different
architectures).
http://www.ime.usp.br/~pjssilva/spot
Now run the following script (you need matplotlib, numpy, Numeric and
NumTut packages):
-- script --
import pylab, numpy, Numeric
from NumTut import view
win = numpy.fromfile('spot').reshape((50,50,3))
pylab.imshow(win)
pylab.show()
view(Numeric.array(win))
raw_input('Press enter to finish')
-- end script --
You should see two big green spots when the image is presented using
matplotlib.
Best,
Paulo
Obs: I am not 

On Monday 21 August 2006 02:27, Jouni K Seppanen wrote:
> Darren Dale <dd...@co...> writes:
> > On Sunday 20 August 2006 10:25 am, Edin Salkovi=C4=87 wrote:
> >> Also, I thought that the author of the current code base did some
> >> design mistakes at the begining. And, being a developer newbie,
> >> it's a lot easier to start things from scratch, than make fixes to
> >> old stuff you don't understand well.
> >
> > Just a general comment. Eric Raymond observed in The Cathedral and
> > the Bazaar that "Good programmers know what to write. Great ones
> > know what to rewrite (and reuse)."
>
> See also: http://www.joelonsoftware.com/articles/fog0000000069.html
>
> >> The point is that, i.e. \cal sets the current fontface to "cal",
> >> and the change is propagated till the end of the current scope (or
> >> untill it hits \rm, for example). Old mathtext applies it only to
> >> the first item after the command.
> >
> > What does this have to do with real TeX? Maybe you could post an
> > example. It is possibly just an mpl bug that needs to be addressed.
>
> Run the attached file through LaTeX to see what he means. Does
> Matplotlib attempt to replicate some subset of (La)TeX syntax exactly,
> or is it just a "TeX-like" syntax?
I think what he meant to say was that old mathtext didnt behave the way TeX=
=20
does, is that correct Edin? My feeling is that mpl should replicate the=20
(La)TeX syntax exactly. Imagine the confusion if mathtext gives one result,=
=20
and usetex gives another.=20

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Darren Dale <dd...@co...> writes:
> On Sunday 20 August 2006 10:25 am, Edin Salković wrote:
>> Also, I thought that the author of the current code base did some
>> design mistakes at the begining. And, being a developer newbie,
>> it's a lot easier to start things from scratch, than make fixes to
>> old stuff you don't understand well.
>
> Just a general comment. Eric Raymond observed in The Cathedral and
> the Bazaar that "Good programmers know what to write. Great ones
> know what to rewrite (and reuse)."
See also: http://www.joelonsoftware.com/articles/fog0000000069.html
>> The point is that, i.e. \cal sets the current fontface to "cal",
>> and the change is propagated till the end of the current scope (or
>> untill it hits \rm, for example). Old mathtext applies it only to
>> the first item after the command.
>
> What does this have to do with real TeX? Maybe you could post an
> example. It is possibly just an mpl bug that needs to be addressed.
Run the attached file through LaTeX to see what he means. Does
Matplotlib attempt to replicate some subset of (La)TeX syntax exactly,
or is it just a "TeX-like" syntax?
-- 
Jouni