[Matplotlib-users] Non-interactive plotting to window?
I have a sizeable number of python data-inspection scripts that work as follows: - read some data, or do something with it - plot the data - query the user on the command line and get a response - do what the user commands. These use the venerable PGPLOT package for the graphics, but this has been static for years and is getting increasingly vulnerable to obsolescence of the supporting packages (e.g., numarray). I'm having a hard time converting these scripts to matplotlib because when you do a show(), the mainloop takes over. It's possible to work around by doing a show() for every plot, and then killing the plot manually, but after a couple of hundred manual kills this gets tiresome. It would also be possible to restructure the code so that the various options get controlled by key press events in the plot, I suppose, but the effort involved in converting all the scripts would be pretty large. So my question: Is there a simple way of getting matplotlib to display a plot in a window and then surrender control to the main program, without destroying the plot? Something like a method to kill mainloop would be ideal. Thanks. [Apologies if this is general knowledge -- I couldn't find an answer.] -- View this message in context: http://old.nabble.com/Non-interactive-plotting-to-window--tp32981792p32981792.html Sent from the matplotlib - users mailing list archive at Nabble.com. -- 10 Tips for Better Server Consolidation Server virtualization is being driven by many needs. But none more important than the need to reduce IT complexity while improving strategic productivity. Learn More! http://www.accelacomm.com/jaw/sdnl/114/51507609/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
[Matplotlib-users] plotting 3D
Hello, I have 2D array where each (x, y) cell represents the height of that point on the Z axis (you can think of it as the map of some mountain chain). I'd like to get the plot_surface() of this data. What I don't understand in particular is the content of the X, Y ,Z array parameter in my particular example. Can anybody elaborate on this please? Thanks! Claudio -- Claudio Martella claudio.marte...@vu.nl -- 10 Tips for Better Server Consolidation Server virtualization is being driven by many needs. But none more important than the need to reduce IT complexity while improving strategic productivity. Learn More! http://www.accelacomm.com/jaw/sdnl/114/51507609/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] Incorrect latex rendering for \hat{x} and \vec{x}
Hi
Latex rendering looks OK here.
In [9]: matplotlib.__version__
Out[9]: '1.0.0'
However, synaptic tells me: 1.0.1-rc1-1ubuntu5.
System Ubuntu 10.10 with ppa
(http://ppa.launchpad.net/bgamari/matplotlib-unofficial/ubuntu) for
matplotlib 1.0.1.
Best,
Peter
Am 07.12.2011 23:06, schrieb Alejandro Weinstein:
Hi:
I am getting incorrect renderings when using \hat{x} or \vec{x}. The
following code
#
import matplotlib.pylab as plt
plt.axes([0.1, 0.15, 0.8, 0.75])
plt.plot(range(10))
plt.xlabel(r'$\hat{y}$ $\vec{x}$ $x^2 + y^2$', fontsize=20)
plt.show()
#
produce the attached plot. Note that the hat and the arrow are in
the wrong place. The other Latex part looks OK.
I am running version 1.2.x (built from commit
11e528425e230a3e23d04202aea23d88d40d9c4c) and Ubuntu 11.10.
Any ideas about how to solve the problem?
Alejandro.
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Re: [Matplotlib-users] plotting 3D
On Tue, Dec 13, 2011 at 1:12 PM, Martella, C. c.marte...@vu.nl wrote: Hello, I have 2D array where each (x, y) cell represents the height of that point on the Z axis (you can think of it as the map of some mountain chain). I'd like to get the plot_surface() of this data. What I don't understand in particular is the content of the X, Y ,Z array parameter in my particular example. Can anybody elaborate on this please? Claudio, X and Y represent the coordinates of the height data (which is Z). X and Y must be the same shape as the Z data. For example: # Create 1-D coordinate arrays x = np.arange(-10, 10, 0.5) # length 40 y = np.arange(-25, 25, 2.5) # length 20 # Create 2-D arrays from the coordinate arrays # The shape of X and Y will be (20, 40) # i.e., 20 rows and 40 columns. X, Y = np.meshgrid(x, y) # This will also have shape of (20, 40) Z = np.sqrt(X**2 + Y**2) ax.plot_surface(X, Y, Z) Now, a more complicated example shows that the X and Y coordinates do not have to be monotonic, but the coordinates must be neighboring in both euclidean space and in the data array, or else the surface will look torn. This example on the website shows how to plot a sphere by using a parametric representation of the surface: http://matplotlib.sourceforge.net/examples/mplot3d/surface3d_demo2.html I hope this helps! Ben Root -- 10 Tips for Better Server Consolidation Server virtualization is being driven by many needs. But none more important than the need to reduce IT complexity while improving strategic productivity. Learn More! http://www.accelacomm.com/jaw/sdnl/114/51507609/___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] Matplotlib-users Digest, Vol 67, Issue 23
Eric, I installed mpl from git (git clone git://github.com/matplotlib/matplotlib.git, unless I was suppose to use one of the branches) and same problem. I looked at my code again and thought there should be a canvas.draw() before calling c.copy_from_bbox(a.bbox), but still the same problem. However, I did have it work the first time I added c.draw() and used the git mpl, and by work I mean that everything stayed visible on the figure. When people start coming in to my work I'll ask them to run my sample code and see what happens. It almost seems like mpl is handling the window activation event funny, is there an easy way to print out the callbacks being used by a mpl figure? For now, I will subclass QApplication, and implement notify() to print out events as they come in, but still...this is just weird. Thanks. -Dave On 12/14/11 10:30 PM, Eric Firing wrote: David, It works for me on linux with mpl from git. I haven't tried to figure it out, but it is conceivable that the problem you are seeing was fixed with this: commit b624546ae60dc5878e75a32f41a160d383548b8f Author: Eric Firingefir...@hawaii.edu Date: Tue Oct 18 08:06:21 2011 -1000 backend_qt4agg: draw() immediately calls FigureCanvasAgg.draw() This is the latest in a series of modifications to the Qt4Agg drawing strategy going back several years. It simplifies the code and should solve the problem introduced in 6938b0025; that is, delaying the Agg draw operation until the paintEvent breaks code expecting that draw operation to have occurred immediately. The problem was reported here: http://sourceforge.net/mailarchive/message.php?msg_id=28245744 Eric -- 10 Tips for Better Server Consolidation Server virtualization is being driven by many needs. But none more important than the need to reduce IT complexity while improving strategic productivity. Learn More! http://www.accelacomm.com/jaw/sdnl/114/51507609/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] Blitting with qt4
Oops forgot to change subject. On 12/15/11 10:02 AM, David Hoese wrote: Eric, I installed mpl from git (git clone git://github.com/matplotlib/matplotlib.git, unless I was suppose to use one of the branches) and same problem. I looked at my code again and thought there should be a canvas.draw() before calling c.copy_from_bbox(a.bbox), but still the same problem. However, I did have it work the first time I added c.draw() and used the git mpl, and by work I mean that everything stayed visible on the figure. When people start coming in to my work I'll ask them to run my sample code and see what happens. It almost seems like mpl is handling the window activation event funny, is there an easy way to print out the callbacks being used by a mpl figure? For now, I will subclass QApplication, and implement notify() to print out events as they come in, but still...this is just weird. Thanks. -Dave On 12/14/11 10:30 PM, Eric Firing wrote: David, It works for me on linux with mpl from git. I haven't tried to figure it out, but it is conceivable that the problem you are seeing was fixed with this: commit b624546ae60dc5878e75a32f41a160d383548b8f Author: Eric Firingefir...@hawaii.edu Date: Tue Oct 18 08:06:21 2011 -1000 backend_qt4agg: draw() immediately calls FigureCanvasAgg.draw() This is the latest in a series of modifications to the Qt4Agg drawing strategy going back several years. It simplifies the code and should solve the problem introduced in 6938b0025; that is, delaying the Agg draw operation until the paintEvent breaks code expecting that draw operation to have occurred immediately. The problem was reported here: http://sourceforge.net/mailarchive/message.php?msg_id=28245744 Eric -- 10 Tips for Better Server Consolidation Server virtualization is being driven by many needs. But none more important than the need to reduce IT complexity while improving strategic productivity. Learn More! http://www.accelacomm.com/jaw/sdnl/114/51507609/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] my pie charts gotta pop!
On Wed, Dec 14, 2011 at 11:34 PM, Benjamin Root ben.r...@ou.edu wrote: On Wednesday, December 14, 2011, Jason Grout jason-s...@creativetrax.com wrote: On 12/14/11 6:33 PM, Justin wrote: Any suggestions or places to find a gorgeous pie chart, let me know... I'd probably use Excel or OpenOffice if I were you. Jason There are some neat effects that can be done with the AGG filter. There should be a page about AGG filters on the website. As for text placement, if it is just a one-off figure, you could explicitly code the placement yourself. It is always hard to judge when to get the general solution, and when to hack out the one-offs. Ben Root The page I was referring to: http://matplotlib.sourceforge.net/examples/pylab_examples/demo_agg_filter.html I could have sworn there was another page that talks about agg filters in further details, but I can't seem to find it. Ben Root -- 10 Tips for Better Server Consolidation Server virtualization is being driven by many needs. But none more important than the need to reduce IT complexity while improving strategic productivity. Learn More! http://www.accelacomm.com/jaw/sdnl/114/51507609/___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] Blitting with qt4
Eric, Good news I think I got it to work. So using the same code I sent you originally, I applied the following changes: 1. Install matplotlib from git (this did fix things that I wasn't noticing) 2. Add c.draw() before c.copy_from_bbox 3. Copy f.bbox instead of a.bbox (I think this makes sense since I want it to hold on to the title,ticks, and labels, a.bbox is only the content inside the axis rectangle) 4. Restore f_bbox, blit f.bbox. ...and it seems to work. The git version of mpl did fix this, although restoring just the a.bbox was only keeping the axis rectangle so it made it look like even worse of a bug. Using the new version I noticed this and then started using f.bbox which seems to work the way I want it. Now, my final question is: Is this actually doing what I want performance-wise. When I blit just f.bbox, is it really only repainting the updated line or is it redrawing most of the figure? If you need a copy of the new version of my test code let me know. Thanks for any more clarity/help you can give. -Dave P.S. Is there a book or tutorial or website where I can learn more about how the rendering/painting of stuff like this works. For example, if I could better understand why your bug fix was needed. On 12/15/11 10:04 AM, David Hoese wrote: Oops forgot to change subject. On 12/15/11 10:02 AM, David Hoese wrote: Eric, I installed mpl from git (git clone git://github.com/matplotlib/matplotlib.git, unless I was suppose to use one of the branches) and same problem. I looked at my code again and thought there should be a canvas.draw() before calling c.copy_from_bbox(a.bbox), but still the same problem. However, I did have it work the first time I added c.draw() and used the git mpl, and by work I mean that everything stayed visible on the figure. When people start coming in to my work I'll ask them to run my sample code and see what happens. It almost seems like mpl is handling the window activation event funny, is there an easy way to print out the callbacks being used by a mpl figure? For now, I will subclass QApplication, and implement notify() to print out events as they come in, but still...this is just weird. Thanks. -Dave On 12/14/11 10:30 PM, Eric Firing wrote: David, It works for me on linux with mpl from git. I haven't tried to figure it out, but it is conceivable that the problem you are seeing was fixed with this: commit b624546ae60dc5878e75a32f41a160d383548b8f Author: Eric Firingefir...@hawaii.edu Date: Tue Oct 18 08:06:21 2011 -1000 backend_qt4agg: draw() immediately calls FigureCanvasAgg.draw() This is the latest in a series of modifications to the Qt4Agg drawing strategy going back several years. It simplifies the code and should solve the problem introduced in 6938b0025; that is, delaying the Agg draw operation until the paintEvent breaks code expecting that draw operation to have occurred immediately. The problem was reported here: http://sourceforge.net/mailarchive/message.php?msg_id=28245744 Eric -- 10 Tips for Better Server Consolidation Server virtualization is being driven by many needs. But none more important than the need to reduce IT complexity while improving strategic productivity. Learn More! http://www.accelacomm.com/jaw/sdnl/114/51507609/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
[Matplotlib-users] how to surpress figure pop out within interactive ipython shell?
Dear matplotlib users,
How can I surpress the figure pop out when I make plot within the ipython
interactive shell?
suppose I make a figure first and I want to save it:
fig=plt.figure()
ax=fig.add_subplot(111)
ax.plot(np.arange(10))
fig.savefig('fig1.png')
###actually above is only an example and usually I use loop to make many
figures.
then I want to check another plot:
plt.plot(np.arange(10))
plt.show()
The problem is, when I use plt.show() to check the recently made plot, all
the figures I saved for the last session will pop out and I have to click
on the close icon to close them one by one,
which can be really annoying
any idea would be greatly appreciated!
cheers,
Chao
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Re: [Matplotlib-users] how to surpress figure pop out within interactive ipython shell?
On Thu, Dec 15, 2011 at 12:33 PM, Chao YUE chaoyue...@gmail.com wrote:
Dear matplotlib users,
How can I surpress the figure pop out when I make plot within the ipython
interactive shell?
suppose I make a figure first and I want to save it:
fig=plt.figure()
ax=fig.add_subplot(111)
ax.plot(np.arange(10))
fig.savefig('fig1.png')
###actually above is only an example and usually I use loop to make many
figures.
Try adding 'plt.close(fig)' after you save the figure, or just plt.close()
if you want to close everything.
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Re: [Matplotlib-users] Incorrect latex rendering for \hat{x} and \vec{x}
On Wed, Dec 14, 2011 at 10:20 AM, Peter Liebetraut peter.liebetr...@imtek.uni-freiburg.de wrote: Hi Latex rendering looks OK here. In [9]: matplotlib.__version__ Out[9]: '1.0.0' Just updated to the last version from github, and now works OK. -- 10 Tips for Better Server Consolidation Server virtualization is being driven by many needs. But none more important than the need to reduce IT complexity while improving strategic productivity. Learn More! http://www.accelacomm.com/jaw/sdnl/114/51507609/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] Endpoint of a text string in a plot?
Thank you Benjamin. Yes, I understand the problem. Thank you for the help. I am able to use Annotate for my specific problem: I want to have a line starting from the end of the text to make the tick labels with a left alignment. However, a feature to get the boundary box would be useful for this, to ensure that the plot is tight. Best regards Keld Benjamin Root-2 wrote: On Wednesday, December 14, 2011, Keld Lundgaard keld.lundga...@gmail.com wrote: Hi How do I get the information about the endpoint of a text element? Example: import matplotlib.pylab as plt text = plt.text(0.5,0.5,'hi') plt.show() In the dataTrans coordinates, where does the text string ends? I have spent some time now trying to solve this, seemingly simple problem, so I appreciate any help a lot! Thanks in advance! / Keld It is actually a very difficult thing to do, and is why mpl does not provide a mechanism to find out until after rendering. The problem is that -- in the general case -- it is not possible to know ahead of time how much space some text will take up for an arbitrary font, style and size. You can have the figure get rendered, and then you can query the text's bounding box, if I understand correctly. Maybe the code for tight_layout() might show how it does this. Ben Root -- 10 Tips for Better Server Consolidation Server virtualization is being driven by many needs. But none more important than the need to reduce IT complexity while improving strategic productivity. Learn More! http://www.accelacomm.com/jaw/sdnl/114/51507609/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users -- View this message in context: http://old.nabble.com/Endpoint-of-a-text-string-in-a-plot--tp32977548p32983153.html Sent from the matplotlib - users mailing list archive at Nabble.com. -- 10 Tips for Better Server Consolidation Server virtualization is being driven by many needs. But none more important than the need to reduce IT complexity while improving strategic productivity. Learn More! http://www.accelacomm.com/jaw/sdnl/114/51507609/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] Non-interactive plotting to window?
2011/12/15 John Thorstensen john.thorsten...@dartmouth.edu: So my question: Is there a simple way of getting matplotlib to display a plot in a window and then surrender control to the main program, without destroying the plot? Something like a method to kill mainloop would be ideal. Just make sure you use interactive mode and get rid of the show calls: import matplotlib.pyplot as plt plt.ion() # set interactive mode plt.plot(foo) # plot something bar() # do stuff while the plot is visible plt.close() # if you want to close the plot window from the script This works in mpl 1.1.0 al least with tkagg, gtkagg and qt4agg backends. Goyo -- 10 Tips for Better Server Consolidation Server virtualization is being driven by many needs. But none more important than the need to reduce IT complexity while improving strategic productivity. Learn More! http://www.accelacomm.com/jaw/sdnl/114/51507609/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
[Matplotlib-users] How can I place a table on a plot in Matplotlib?
I'm not having any success in getting the matplotlib table commands to work. Here's an example of what I'd like to do: Can anyone help with the table construction code? Thanks import pylab as plt plt.figure() ax=plt.gca() y=[1,2,3,4,5,4,3,2,1,1,1,1,1,1,1,1] plt.plot([10,10,14,14,10],[2,4,4,2,2],'r') col_labels=['col1','col2','col3'] row_labels=['row1','row2','row3'] table_vals=[11,12,13,21,22,23,31,32,33] # the rectangle is where I want to place the table plt.text(11,4.1,'Table Title',size=8) plt.plot(y) plt.show() -- 10 Tips for Better Server Consolidation Server virtualization is being driven by many needs. But none more important than the need to reduce IT complexity while improving strategic productivity. Learn More! http://www.accelacomm.com/jaw/sdnl/114/51507609/___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] Plot Fill with Jacobian Coordinates
On Tue, Dec 13, 2011 at 7:12 PM, Alex Naysmith yeoman.pyt...@gmail.comwrote: On Mon, Dec 12, 2011 at 7:03 PM, Benjamin Root ben.r...@ou.edu wrote: On Sat, Dec 10, 2011 at 10:36 AM, Alex Naysmith yeoman.pyt...@gmail.comwrote: Hello, I'm trying to plot the stresses in colour of a strained isoparametric element. I have a six noded triangle with vertice coordinates [(xa1,ya1),(xa2,ya2),(xa3,ya3)] = pos_a This triangle deforms and the new coordinate positions are [(xb1,yb1),(xa2,yb2),(xb3,yb3)] = pos_b The remaining nodes are mid nodes also with rest and deformed coordinate positions. To plot the edges of the triangle I use a Jacobian transformation function so that the coordinates of the triangle are in Jacobian coordinates xi1 and xi2 (with xi3 = 1 - xi1 - xi2). This is required as the elements are quadratic with mid-nodes. Each interval is hard coded so that: xi1 = [1.0,0.9,0.8,0.7,0.6,0.5, etc..] xi2 = [0.0,0.1,0.2,0.3,0.4,0.5, etc..] I would like to plot the strains in colour so that the interior of the triangle is filled but I don't want to hard code the Jacobian intervals as this seems an awkward way of doing it. With strain as a function of xi1 and xi2, How can matplotlib provide a continuous interior strain plot of the triangle for all the xi1 and xi2 values from 0 to 1? Regards Alex Naysmith Alex, Perhaps if you can provide an example figure, we might be able to better help you. Right now, I am having trouble envisioning what you describe. Ben Root Ben, I have created a script that uses one isoparametric triangle as an example. The triangle nodes undergo a displacement, resulting in strains inside the triangle. The new script calculates the strains inside the triangle for a range of xi1 and xi2 barycentric coordinates and returns the global coordinates with the corresponding strain. I would like matplotlib to give me a nice interpolated colour plot of the strains inside the triangle, but as the output global coordinates are not aligned in neat rows and columns, I cannot do a straightforward meshgrid plot with imshow. http://bazaar.launchpad.net/~eckeroo/misc/mpl_scripts/files There are further comments in the script that may explain things better. I want a figure like this: http://matplotlib.sourceforge.net/examples/pylab_examples/animation_demo.html But for a 6 noded quadratic triangle instead of square. The intention is to have all the triangles in the mesh display their strains with interpolated colours. Regards Alex Hello, I tried using contour and now I have a figure! http://bazaar.launchpad.net/~eckeroo/misc/mpl_scripts/view/head:/figure.png I can now show clearly what I'm aiming for with this figure. I want the contour fill to remain inside the triangle. There will be a whole mesh of triangles to fill. The updated sample script is here: http://bazaar.launchpad.net/~eckeroo/misc/mpl_scripts/view/head:/triangle_fill_v2.py I arranged my data points into square X and Y arrays along with the strains in the Z array and then simply P.contourf(X, Y, Z) As the figure shows, it's not there yet as a couple of the corners aren't filled in and there's a big fill outside the triangle. I think this is due to difficulties in translating points from the natural triangle coordinates (barycentric) to the x,y coordinates. But the contour looks correct as it's interpolated between the strain points. Regards Alex -- 10 Tips for Better Server Consolidation Server virtualization is being driven by many needs. But none more important than the need to reduce IT complexity while improving strategic productivity. Learn More! http://www.accelacomm.com/jaw/sdnl/114/51507609/___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] Plot Fill with Jacobian Coordinates
On Thu, Dec 15, 2011 at 3:18 PM, Alex Naysmith yeoman.pyt...@gmail.comwrote: On Tue, Dec 13, 2011 at 7:12 PM, Alex Naysmith yeoman.pyt...@gmail.comwrote: On Mon, Dec 12, 2011 at 7:03 PM, Benjamin Root ben.r...@ou.edu wrote: On Sat, Dec 10, 2011 at 10:36 AM, Alex Naysmith yeoman.pyt...@gmail.com wrote: Hello, I'm trying to plot the stresses in colour of a strained isoparametric element. I have a six noded triangle with vertice coordinates [(xa1,ya1),(xa2,ya2),(xa3,ya3)] = pos_a This triangle deforms and the new coordinate positions are [(xb1,yb1),(xa2,yb2),(xb3,yb3)] = pos_b The remaining nodes are mid nodes also with rest and deformed coordinate positions. To plot the edges of the triangle I use a Jacobian transformation function so that the coordinates of the triangle are in Jacobian coordinates xi1 and xi2 (with xi3 = 1 - xi1 - xi2). This is required as the elements are quadratic with mid-nodes. Each interval is hard coded so that: xi1 = [1.0,0.9,0.8,0.7,0.6,0.5, etc..] xi2 = [0.0,0.1,0.2,0.3,0.4,0.5, etc..] I would like to plot the strains in colour so that the interior of the triangle is filled but I don't want to hard code the Jacobian intervals as this seems an awkward way of doing it. With strain as a function of xi1 and xi2, How can matplotlib provide a continuous interior strain plot of the triangle for all the xi1 and xi2 values from 0 to 1? Regards Alex Naysmith Alex, Perhaps if you can provide an example figure, we might be able to better help you. Right now, I am having trouble envisioning what you describe. Ben Root Ben, I have created a script that uses one isoparametric triangle as an example. The triangle nodes undergo a displacement, resulting in strains inside the triangle. The new script calculates the strains inside the triangle for a range of xi1 and xi2 barycentric coordinates and returns the global coordinates with the corresponding strain. I would like matplotlib to give me a nice interpolated colour plot of the strains inside the triangle, but as the output global coordinates are not aligned in neat rows and columns, I cannot do a straightforward meshgrid plot with imshow. http://bazaar.launchpad.net/~eckeroo/misc/mpl_scripts/files There are further comments in the script that may explain things better. I want a figure like this: http://matplotlib.sourceforge.net/examples/pylab_examples/animation_demo.html But for a 6 noded quadratic triangle instead of square. The intention is to have all the triangles in the mesh display their strains with interpolated colours. Regards Alex Hello, I tried using contour and now I have a figure! http://bazaar.launchpad.net/~eckeroo/misc/mpl_scripts/view/head:/figure.png I can now show clearly what I'm aiming for with this figure. I want the contour fill to remain inside the triangle. There will be a whole mesh of triangles to fill. The updated sample script is here: http://bazaar.launchpad.net/~eckeroo/misc/mpl_scripts/view/head:/triangle_fill_v2.py I arranged my data points into square X and Y arrays along with the strains in the Z array and then simply P.contourf(X, Y, Z) As the figure shows, it's not there yet as a couple of the corners aren't filled in and there's a big fill outside the triangle. I think this is due to difficulties in translating points from the natural triangle coordinates (barycentric) to the x,y coordinates. But the contour looks correct as it's interpolated between the strain points. Regards Alex Alex, Just curious, have you checked to see if tricontourf() meets your needs? http://matplotlib.sourceforge.net/api/axes_api.html?highlight=tricontourf#matplotlib.axes.Axes.tricontourf Ben Root -- 10 Tips for Better Server Consolidation Server virtualization is being driven by many needs. But none more important than the need to reduce IT complexity while improving strategic productivity. Learn More! http://www.accelacomm.com/jaw/sdnl/114/51507609/___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] How to do million data-point plots with Matplotlib?
On 12/10/2011 01:12 PM, David Smith wrote: I have been working on a program that uses Matplotlib to plot data consisting of around one million points. Sometimes the plots succeed but often I get an exception: OverFlowError: Agg rendering complexity exceeded. Are you sure path simplification is running? (i.e. the rcParam path.simplify is True)? That generally does a good job of removing excess points on the fly. You shouldn't need a development version for this to work. 0.99.x or later should be adequate. You're not going to see a million points at typical screen resolutions anyway. I can make this message go away by plotting the data in chunks as illustrated in the demo code below. However, the extra code is a chore which I don't think should be necessary - I hope the developers will be able to fix this issue sometime soon. I know that the development version has some modifications to addressing this issue. I wonder if it is expected to make the problem go away? By the way, this plot takes about 30 seconds to render on my I7 2600k. The main program reaches the show() statement quickly and prints Done plotting?. Then I see that the program reaches 100% usage on one CPU core (4 real, 8 virtual on the 2600k) until the plot is displayed. I wonder if there is any way to persuade Matplotlib to run some of the chunks in parallel so as to use more CPU cores? That would be great, but very difficult. The Python parts of the problem are tricky to parallelize due to the GIL. The Agg part of the problem will be difficult to parallelize unless there is a trivial way to chuck the plotted lines into parts before stroking -- each chunk could be rendered to its own buffer and then blended together in a final step. But all that is academic at this point -- there's no code to do such a thing now. Plotting something other than random data, the plots run faster and the maximum chunk size is smaller. The maximum chunk size also depends on the plot size - it is smaller for larger plots. I am wondering if I could use this to plot course and fine versions of the plots. The course plot is zoomed in version of the small-sized raster. That would be better than decimation as all the points would at least be there. I think what you're seeing is the effect of the path simplification algorithm. The number of points that it removes depends on the density of the points and the resolution of the output image. It's hard to predict exactly how many points it will remove. Mike Thanks in advance, David --- start code - ## Demo program shows how to chunk plots to avoid the exception: ## ##OverflowError: Agg rendering complexity exceeded. ##Consider downsampling or decimating your data. ## ## David Smith December 2011. from pylab import * import numpy as np nPts=600100 x = np.random.rand(nPts) y = np.random.rand(nPts) ## This seems to always succeed if Npts= 2, but fails ## for Npts 3. For points between, it sometimes succeeds ## and sometimes fails. figure(1) plot (x, y) ## Chunking the plot alway succeeds. figure(2) chunk_size=2 iStarts=range(x.size/chunk_size) for iStart in iStarts: print Plotting chunk starting at %d\n % iStart plot(x[iStart:iStart+chunk_size], y[iStart:iStart+chunk_size], '-b') left_overs = nPts % chunk_size if left_overs 0: print Leftovers %d points\n % left_overs plot(x[-left_overs-1:], y[-left_overs-1:], '-r') print done plotting? show() -- end code Please don't reply to this post It is rediculous to plot 1 million points on screen. I am routinely capturing million-point traces from oscilloscopes and other test equipment and to I need to be able to spot features in the data (glitches if you will) that may not show up plotting decimated data. I can then zoom the plot to inspect these features. -- Learn Windows Azure Live! Tuesday, Dec 13, 2011 Microsoft is holding a special Learn Windows Azure training event for developers. It will provide a great way to learn Windows Azure and what it provides. You can attend the event by watching it streamed LIVE online. Learn more at http://p.sf.net/sfu/ms-windowsazure ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users -- Learn Windows Azure Live! Tuesday, Dec 13, 2011 Microsoft is holding a special Learn Windows Azure training event for developers. It will provide a great way to learn Windows Azure and what it provides. You can attend the event by watching it streamed LIVE online. Learn more at http://p.sf.net/sfu/ms-windowsazure
