matplotlib-users Mailing List for matplotlib

Hi,

Here's another fractal music video, made with matplotlib:

https://www.youtube.com/watch?v=ANftKlKDtXc

Enjoy!

--Prahas

Le mardi 14 avril 2015 à 18:15 +0800, oyster a écrit :
> I am using anaconda(Python 2.7.6 |Anaconda 1.9.2 (32-bit)| (default,
> Nov 11 2013, 10:50:31) [MSC v.1500 32 bit (Intel)] on win32) on
> windows 7 64 bits
> And the matplotlib is 1.4.3, numpy is 1.9.2, and scipy is 0.15.1,
> which are all been updated by 'conda update xx'
> 
> As http://matplotlib.org/api/pyplot_api.html says
> [quote]
> matplotlib.pyplot.imread(*args, **kwargs) Read an image from a file
> into an array.
> 
> Return value is a numpy.array. For grayscale images, the return array
> is MxN. For RGB images, the return value is MxNx3. For RGBA images the
> return value is MxNx4.
> [/quote]
> 
> But if I read a 128*128*8 BPP gray PNG file, the array.shape is (128,
> 128, 3); if I read a 128*128*24BPP color PNG file, the array.shape is
> (128, 128, 4)

Are you sure your png "24bpp" does not have a transparency channel?

-- 
Fabrice

I am using anaconda(Python 2.7.6 |Anaconda 1.9.2 (32-bit)| (default,
Nov 11 2013, 10:50:31) [MSC v.1500 32 bit (Intel)] on win32) on
windows 7 64 bits
And the matplotlib is 1.4.3, numpy is 1.9.2, and scipy is 0.15.1,
which are all been updated by 'conda update xx'

As http://matplotlib.org/api/pyplot_api.html says
[quote]
matplotlib.pyplot.imread(*args, **kwargs) Read an image from a file
into an array.

Return value is a numpy.array. For grayscale images, the return array
is MxN. For RGB images, the return value is MxNx3. For RGBA images the
return value is MxNx4.
[/quote]

But if I read a 128*128*8 BPP gray PNG file, the array.shape is (128,
128, 3); if I read a 128*128*24BPP color PNG file, the array.shape is
(128, 128, 4)

Why? Thanks

[code]
from pylab import *

imgGrayPng=imread('python-gray.png')
print (imgGrayPng.shape)    #(128, 128, 3)


imgGrayJpg=imread('python-gray.jpg')
print (imgGrayJpg.shape)    #(128, 128)


imgColorPng=imread('python-color.png')
print (imgColorPng.shape)  #(128, 128, 4)


imgColorJpg=imread('python-color.jpg')
print (imgColorJpg.shape) #(128, 128, 3)


[/code]

Hi Ryan,
wow! This tutorial is one of the best I ever encountered. Nothing is missing, nothing is cryptic or unclear. What I like best is, that it get's along without using Qt Designer plugins or something similar strange. It's a good basis to start. Maybe you should write a book, covering all the untold things one needs to solve problems like that. I browsed through plenty of books the last weeks and what really is missing, is a cookbook about Qt Designer, Glade and wxWidgets and how to fill it with python3 and it's lib's like matplotlib, pyqtgraph, numpy, sympy etc.
I would buy it right away!cheers,Christian
 --
"A little learning never caused anyone's head to explode!"

"Ein wenig Lernen hat noch niemandens Kopf zum Explodieren gebracht!" 


     On Friday, April 10, 2015 7:14 PM, Ryan Nelson <rne...@gm...> wrote:
   

 Christian,
As it turns out, I wrote a blog post (for my terrible blog) about using Designer to create a MPL based GUI (http://blog.rcnelson.com/building-a-matplotlib-gui-with-qt-designer-part-1/). I was going to write this up for the MPL docs... But it got really long (3 parts), so I just used my personal site. It got so long because this was the second time I needed to figure this out, and I wanted to make a very detailed outline for my own future reference. Unfortunately, I don't have any experience with Qt5, but I imagine things are similar. I think they just rearranged the locations of some of the widgets, but I'd be curious to hear your experience. I gave up on PyQtdesignerplugins. I think it makes more sense to just use a generic widget as the MPL container. 
I would be very happy if you had comments for my Qt designer posts.
Ryan
On Wed, Apr 8, 2015 at 5:47 AM, Christian Ambros <am...@ym...> wrote:

Hi Ryan,
could you write down, as a tutorial, how you built the example with the qt designer?In the last hours I read all most everything what can be found on the issue of getting matplotlib running with pyqt5 and the designer but as you realized yourself, there is little to be found handy.
I'm stuck at a project, which has to use python3, and pyqt5 and am not allowed by my boss to fall back to pyqt4 or qt_compat. He wants to make sure that we use the latest revisions.
So I#m very pleased to read that someone already set food on this terrain. 
Qt5.4.1 is running and I installed PyQtdesingerplugins, in mind that they were written for PyQt4. Are they usable in 5? I added the env-variables to my bashrc, did get any changes shown in the designer. Of course I did a re-log-in to start fresh, but any changes were noteable.What possible ways of embedding matplotlib into a designer base pyqt5-gui else, are there?
cheers,Christian


 --
"A little learning never caused anyone's head to explode!"

"Ein wenig Lernen hat noch niemandens Kopf zum Explodieren gebracht!" 


     On Wednesday, February 18, 2015 11:59 PM, Ryan Nelson <rne...@gm...> wrote:
   

 Hello list,
A couple months ago, I spent quite a bit of time trying to figure out how to use Qt designer create a GUI with an embedded MPL window. Unfortunately, the Scipy cookbook page (http://wiki.scipy.org/Cookbook/Matplotlib/Qt_with_IPython_and_Designer) is very outdated. A recent post (http://matplotlib.1069221.n5.nabble.com/Re-Keep-list-of-figures-or-plots-and-flip-through-list-using-UI-td44961.html) brought up some questions about a use case very similar to mine, so I redid my example and was going to write a quick tutorial for the docs.
Unfortunately, I'm not a Qt guru, so I thought that I would ask on the list for some advice.  The OP and I were both interested in being able to have a list of figures that you could select from to change the plot window. The embedding examples in the docs create subclasses of FigureClass* and embed the plotting figure/axes/etc. This works but gets tricky, though, when trying to switch plots. Also, for interactive IPython work, I didn't like that the plotting objects were mixed in with all the QtGui.QWidget attributes, which makes introspective searching painful. My solution was to create a dictionary of matplotlib.figure.Figure objects that had all of the plotting stuff defined. Then when I select a new plot from the list, the old one is removed and a new FigureClass object is created using the selected Figure object. Has anyone else successfully done something like this? Is there a better way? Also, it seems if I zoom the current plot, change to a new plot, and change back, the zoom region is retained. Anyone know how to reset the zoom region?
Attached is my example: "window.py" is the Designer-created main window and "custommpl.py" is the subclass of the main window that I wrote. It's about as short as I could make it.

Thanks
Ryan


------------------------------------------------------------------------------
Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server
from Actuate! Instantly Supercharge Your Business Reports and Dashboards
with Interactivity, Sharing, Native Excel Exports, App Integration & more
Get technology previously reserved for billion-dollar corporations, FREE
http://pubads.g.doubleclick.net/gampad/clk?id=190641631&iu=/4140/ostg.clktrk
_______________________________________________
Matplotlib-users mailing list
Mat...@li...
https://lists.sourceforge.net/lists/listinfo/matplotlib-users