Mailman 3 November 2015 - Matplotlib-users

Error on import matplotlib.pyplot (on Anaconda3 for Windows 10 Home 64-bit PC)
by anshul6 Dec. 4, 2015

Dec. 4, 2015

Hello, I just installed "Anaconda3 for Windows v2.4.0" on my Windows 10 Home (64 bit) machine. (Downloaded the Windows 64-bit Graphical Installer "Anaconda3-2.4.0-Windows-x86_64.exe" (392 MB) from https://www.continuum.io/downloads) In a Command Prompt window, I did the conda "Test Drive", including "conda update conda", etc, and in the end see the following: The installation seems to have been successful: However, I get an error message when I try to import "matplotlib.pyplot" as below (note that matplotlib appears to be imported fine): I opened "C:\Anaconda3\lib\site-packages\matplotlib\font_manager.py" in a text editor and tried to look for the source of the error. I think this is where things are going wrong: But I'm at a loss as to why this is happening, and how to rectify it. Please help. Thanks, Anshul -- View this message in context: http://matplotlib.1069221.n5.nabble.com/Error-on-import-matplotlib-pyplot-o… Sent from the matplotlib - users mailing list archive at Nabble.com.

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exporting tricontour function results
by Francis Chabouis Dec. 3, 2015

Dec. 3, 2015

Hello, I'm having some difficulties with the results of the tricontour function. What I'm trying to achieve is fairly simple : I'd like to export the results of the tricontour function as a geoJson. (I think a function doing exactly this job would be nice to have in the library). I wrote this : cs = plt.tricontourf(t, v, levels) for i,collection in enumerate(cs.collections): for path in collection.get_paths(): Now I have this path object. My first problem : when I check the number of vertices (via len(path.vertices)) I get 732 vertices. If I try to access those vertices with iter_segments as recommended in the doc, I get only 125 vertices. seg = path.iter_segments() print len(list(seg)) ==> 125 Am I doing something wrong, or is it possibly a bug ? My second problem : geoJson works with interior and exterior rings. To describe a polygon with a hole in it, we first declare a closed line (that will be the exterior) and all the subsequent lines will be the "holes" (interiors). It seems that what I get from iter_segments and to_polygons is a bunch of lines, but there is no way to know which is an interior, which is an exterior. But I guess this must be stored somewhere as MPL is able to draw a graph from this information ! Any hints on how I should proceed ? Let me know if you need additional information. Thanks ps : I got some of my infos from this thread : http://matplotlib.1069221.n5.nabble.com/Structure-of-contour-object-returne… ps2 : If I can write this function I would be happy to integrate it in the lib if you're interested.

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Some beginner questions
by David Aldrich Dec. 1, 2015

Dec. 1, 2015

Hi I'm new to Matplotlib and am struggling a bit. I'm using Matplotlib with the Kivy GUI framework, but that shouldn't be directly relevant. I want to show a single figure having 4 subplots, each displaying one line. My code looks like this (simplified): class CMplGraph(): pass def __init__(self, **kwargs): self.create_plot() def create_plot(self): self.fig, ((self.ax0, self.ax1), (self.ax2, self.ax3)) = plt.subplots(nrows=2, ncols=2) self.ax0.set_title("Title_0") self.ax1.set_title("Title_1") self.ax2.set_title("Title_2") self.ax3.set_title("Title_3") plt.show() def plot(self, plotType, xCoords, yCoords): if (plotType == "PLOT_0 "): ax = self.ax0 elif (plotType == " PLOT_1"): ax = self.ax1 elif (plotType == " PLOT_2"): ax = self.ax2 elif (plotType == " PLOT_3"): ax = self.ax3 else: raise BadPlotType(plotType) # remove previous line if len(ax.lines) > 0: ax.lines.pop(0) plt.draw() time.sleep(1) # Blink line = ax.plot(xCoords, yCoords, color='blue') canvas = self.fig.canvas canvas.draw() Then my main app can call create_plot() once, followed by plot() whenever it wants to update the displayed data. This seems to work but I'm not sure I'm doing it correctly. Here are my questions: 1) Is it ok that I created axis objects? 2) Am I removing the previous line correctly? 3) I would like display to 'blink' between successive calls to plot(). So I put in a 1s sleep after removing the previous line. There should therefore be a flash before the new data is displayed. But I don't see that blink - the line updates instantaneously. Why is that? Best regards David

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Embed LassoSelector and Quiver
by Hypnus1803 Dec. 1, 2015

Dec. 1, 2015

Hello everyone, I want to know if I could embed LassoSelector function with Quiver. More precise, I want to make a mask using LassoSelector selection. Thanks. -- View this message in context: http://matplotlib.1069221.n5.nabble.com/Embed-LassoSelector-and-Quiver-tp46… Sent from the matplotlib - users mailing list archive at Nabble.com.

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Axis labels along y-axis
by pikachu Dec. 1, 2015

Dec. 1, 2015

I would like to have the axis labels along the y-axis for this sample. How can I do it? http://matplotlib.org/examples/pylab_examples/colorbar_tick_labelling_demo.… -- View this message in context: http://matplotlib.1069221.n5.nabble.com/Axis-labels-along-y-axis-tp46417.ht… Sent from the matplotlib - users mailing list archive at Nabble.com.

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How to center axes intersecting at (0,0)
by sh77 Dec. 1, 2015

Dec. 1, 2015

Hi, I'm new to matplotlib. I would like to do something very simple. In the figure created by the following code, I would like the axes to be centered in the figure and intersecting at point (0,0): import matplotlib.pyplot as plt plt.plot([1,2,3,4], [1,-4,9,-16], 'ro') plt.axis([-6, 6, -20, 20]) plt.title('Title') plt.show() Can you please give me the simplest lines of code to achieve this? (the hints to solutions that I have seen over the internet are amazingly complex for such a simple task) Many thanks saikari -- View this message in context: http://matplotlib.1069221.n5.nabble.com/How-to-center-axes-intersecting-at-… Sent from the matplotlib - users mailing list archive at Nabble.com.

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Matplotlib, Python 3.5.0 and RHEL 5
by Derek Wallace Dec. 1, 2015

Dec. 1, 2015

Hi, IT are trying to install matplot lib (1.5.0) for Python 3.5.0. They have it working on RHEL6 machines and claim it doesn't/cant/wont work on RHEL 5 machines. I don't have specific information from them why or what made them come to that conclusion. However when I try running I get the following. $ /depot/Python-3.5.0/bin/python Python 3.5.0 (default, Oct 15 2015, 22:50:34) [GCC 4.1.2 20080704 (Red Hat 4.1.2-48)] on linux Type "help", "copyright", "credits" or "license" for more information. >>> import matplotlib >>> print(matplotlib.__version__) 1.5.0 >>> import matplotlib.pyplot as plt Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/depot/Python-3.5.0/lib/python3.5/site-packages/matplotlib/pyplot.py", line 29, in <module> import matplotlib.colorbar File "/depot/Python-3.5.0/lib/python3.5/site-packages/matplotlib/colorbar.py", line 32, in <module> import matplotlib.artist as martist File "/depot/Python-3.5.0/lib/python3.5/site-packages/matplotlib/artist.py", line 14, in <module> from .transforms import (Bbox, IdentityTransform, TransformedBbox, File "/depot/Python-3.5.0/lib/python3.5/site-packages/matplotlib/transforms.py", line 39, in <module> from matplotlib._path import (affine_transform, count_bboxes_overlapping_bbox, ImportError: /depot/Python-3.5.0/lib/python3.5/site-packages/matplotlib/_path.cpython-35m-x86_64-linux-gnu.so: ELF file OS ABI invalid Can anyone tell me if RHEL 5.x is supported or not? Can anyone throw any light on the above error message. Thx Derek

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New Programmer Looking for Places to Help
by Unprecedented Owl Dec. 1, 2015

Dec. 1, 2015

Hi matplotlib community, I'm a new programmer who is familiar with Python and uses GitHub. How do you suggest I can make myself useful in this open source project? -- View this message in context: http://matplotlib.1069221.n5.nabble.com/New-Programmer-Looking-for-Places-t… Sent from the matplotlib - users mailing list archive at Nabble.com.

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Re: [Matplotlib-users] Matplotlib-users Digest, Vol 4, Issue 20
by Alain Muls Nov. 24, 2015

Nov. 24, 2015

Hi Paul, I use virtualenv installed as 'user'. For this project I have the following packages installed on both 64 and 32 bit systems. (pyEphem) [513] [amuls@gnssfield: /home/amuls/amPython/pyEphem]$ pip freeze cycler==0.9.0 matplotlib==1.5.0 numpy==1.10.1 pyephem==3.7.6.0 pyparsing==2.0.5 PySide==1.2.4 python-dateutil==2.4.2 pytz==2015.7 requests==2.8.1 six==1.10.0 wheel==0.24.0 Everything is OK on 32bit Ubuntu 14.04 while the core dump occurs on the 64 bit Ubuntu 14.04 I changed the matplotlib on 64 bit system to 1.4.3 and now I do not have a problem, but the 1.5 matplotlib causes the error. Tx/ALain *Please take note of new phone number since 1 April 2015* ------------------------------ *Alain Muls* *alain.muls(a)rma.ac.be <alain.muls(a)rma.ac.be>* Royal Military Academy - Department CISS Phone +32 2 441 39 36 Renaissance Avenue 30 B1000 Brussels (Belgium) http://www.rma.ac.be/ciss/ http://www.sic.rma.ac.be/ ------------------------------ On 23 November 2015 at 18:00, <matplotlib-users-request(a)python.org> wrote: > Send Matplotlib-users mailing list submissions to > matplotlib-users(a)python.org > > To subscribe or unsubscribe via the World Wide Web, visit > https://mail.python.org/mailman/listinfo/matplotlib-users > or, via email, send a message with subject or body 'help' to > matplotlib-users-request(a)python.org > > You can reach the person managing the list at > matplotlib-users-owner(a)python.org > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of Matplotlib-users digest..." > > > Today's Topics: > > 1. pyplot problem between 62bit and 32bit system (Alain Muls) > 2. Re: pyplot problem between 62bit and 32bit system (Paul Hobson) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Mon, 23 Nov 2015 12:16:24 +0100 > From: Alain Muls <alain.muls(a)gmail.com> > To: matplotlib-users(a)python.org > Subject: [Matplotlib-users] pyplot problem between 62bit and 32bit > system > Message-ID: > <CAMKve_rWAzmp1aLyn7Q5xN2bpsCW2Y5gspD4y+u= > hnTPi-u_jg(a)mail.gmail.com> > Content-Type: text/plain; charset="utf-8" > > Hi > > I have a problem with a script that fails on my 64bit system, but runs > well on a 32bit system. > I get a core dump at > > import matplotlib.pyplot as plt > ... > ... > fig = plt.figure(figsize=(20.0, 16.0)) > (core dump) > > Any ideas? > > Tx/Alain > > *Please take note of new phone number since 1 April 2015* > ------------------------------ > *Alain Muls* *alain.muls(a)rma.ac.be <alain.muls(a)rma.ac.be>* Royal Military > Academy - Department CISS Phone +32 2 441 39 36 Renaissance Avenue 30 > B1000 Brussels (Belgium) > > http://www.rma.ac.be/ciss/ > http://www.sic.rma.ac.be/ > ------------------------------ >

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Re: [Matplotlib-users] Two circles with “exponential decay” coloring, and alpha < 1, having trouble with color mixing?
by Thomas Caswell Nov. 24, 2015

Nov. 24, 2015

Please keep all emails on-list. I am actually not sure this is possible. The problem is even if the background is transparent, the first image is still composited on to it first, thus the bottom value still comes in with alpha ** 2 when the second layer is added. Why are you trying to do this? You might be a better to add your data into one image and then use shapely to compute the union of the paths for clipping. Tom On Mon, Nov 23, 2015 at 8:07 PM Brian Merchant <bhmerchant(a)gmail.com> wrote: > Hi Thomas, > > Ah, so should I somehow set the background to be transparent? Put another > way, how would I remove the influence of the background on the compositing? > > On Mon, Nov 23, 2015 at 2:41 PM, Thomas Caswell <tcaswell(a)gmail.com> > wrote: > >> The way we do the alpha blending, the output value is (alpha * v1) + >> ((alpha-1) * v2). All of the artists are compsited down on top of a white >> background so the compositing is not commutative. >> >> (a * .5) + (.5 * (b * .5 + .5)) =/= (b * .5) + (.5 * (a * .5 + .5)) >> >> >> On Mon, Nov 23, 2015 at 1:55 PM Sterling Smith <smithsp(a)fusion.gat.com> >> wrote: >> >>> Maybe the issue is with the colormap not having an alpha? Does this >>> >>> http://stackoverflow.com/questions/10127284/overlay-imshow-plots-in-matplot… >>> help? >>> >>> Otherwise, you might file a bug at >>> https://github.com/matplotlib/matplotlib/issues/new >>> >>> -Sterling >>> >>> On Nov 20, 2015, at 4:46PM, Brian Merchant <bhmerchant(a)gmail.com> wrote: >>> >>> > Hi all, >>> > >>> > In order to get circles such that their coloring is radially >>> symmetric, with center being the darkest, and exponential decay in color as >>> one moves farther away from the center along the radius, I used imshow with >>> clip_path using Circle patches. >>> > >>> > Here's a toy script that overlaps two such circles: >>> https://gist.github.com/bmer/7063cc2dd09f1b80a252 >>> > >>> > As you can see if you run the script (or, if you follow this link: >>> http://i.imgur.com/H9jEAZ3.png), even though the alpha is set at 0.5, >>> there doesn't seem to be proper "color mixing" occurring (we should see a >>> result that is symmetric along the x-axis). >>> > >>> > Why is that, and what could I do to fix this issue? >>> > >>> > Kind regards, >>> > Brian >>> > >>> ------------------------------------------------------------------------------ >>> > _______________________________________________ >>> > Matplotlib-users mailing list >>> > Matplotlib-users(a)lists.sourceforge.net >>> > https://lists.sourceforge.net/lists/listinfo/matplotlib-users >>> >>> >>> >>> ------------------------------------------------------------------------------ >>> Go from Idea to Many App Stores Faster with Intel(R) XDK >>> Give your users amazing mobile app experiences with Intel(R) XDK. >>> Use one codebase in this all-in-one HTML5 development environment. >>> Design, debug & build mobile apps & 2D/3D high-impact games for multiple >>> OSs. >>> http://pubads.g.doubleclick.net/gampad/clk?id=254741551&iu=/4140 >>> _______________________________________________ >>> Matplotlib-users mailing list >>> Matplotlib-users(a)lists.sourceforge.net >>> https://lists.sourceforge.net/lists/listinfo/matplotlib-users >>> >> >

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