[Matplotlib-users] custom color cycle from cmap
Hi, I'm trying to plot a set of lines, 12 to be exact, and the default color cycle only supports 8 or 9 distinct colors. That said, I looked up the color maps and segmented it using 12 constant intervals with the hope of getting 12 distinct colors. The problem I'm running in to is that some of the line colors I get are too close to each other. This is because come shades in the colormap have a broader spectrum than others. Here is my code to set my custom default color cycle: import matplotlib as mpl cmap = mpl.cm.get_cmap(name='spectral') #I gues we can also use hsv or gist_rainbow nColors = 12 #number of colors incr = 0.9 / nColors self.mycolors = [] for i in np.arange(0,0.9,incr): self.mycolors.append(cmap(i)) mpl.axes.set_default_color_cycle(self.mycolors) Can anyone suggest a cleaner method? Or is there perhaps an existing class to provide distinct color lines? Thanks, Krishna -- View this message in context: http://old.nabble.com/custom-color-cycle-from-cmap-tp28177653p28177653.html Sent from the matplotlib - users mailing list archive at Nabble.com. -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] Basemap white space
Sorry, my bad. I always hit reply without checking... it is not the first time did that, Here is the solution for the list sake: trim image import StringIO, Image imgdata = StringIO.StringIO() fig.savefig(imgdata, dpi=300, format='png') imgdata.seek(0) im = Image.open(imgdata) def trim(im, border): from PIL import ImageChops bg = Image.new(im.mode, im.size, border) diff = ImageChops.difference(im, bg) bbox = diff.getbbox() if bbox: return im.crop(bbox) else: # found no content raise ValueError(cannot trim; image was empty) im = trim(im,'white') im.show() The StringIO trick is a copy-and-paste from the matplotlib faq. And the trim function I got from here: http://mail.python.org/pipermail/image-sig/2008-July/005092.html Thanks for the discussion, I learned a lot abouth the Agg backend. BTW: What I meant by limitation is the fact that Agg has no GUI like the nice QT window I was using before. The users of this script have no experience with scripting languages and enjoyed choosing the format and filename using a GUI interface. In addition, PIL's show() use an external linux program xv. In the end I wanted to eliminate one external linux program (Imagemagik convert) but ended up with another one... Best, Filipe On 04/06/2010 05:01 PM, Friedrich Romstedt wrote: 2010/4/5 Filipe Fernandes ocef...@gmail.com: Thanks a lot. In the end the StringIO-solution worked fine. The only limitation is that this works only for the Agg backend. [...] I'm happy to hear this. As far as I know, using the Agg backend is not a limitation, because it provides fully anti-aliased output. Besides being available on all platforms (?). Let me make a small hint: The matplotlib-users mailing list is configured that by default replies go to the sender only, not to matplotlib-users, so maybe you want to let the list know about your solution? Anyway I'm happy for your Thanks, so thanks too, Friedrich -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] custom color cycle from cmap
On Apr 8, 2010, at 8:13 AM, KrishnaPribadi wrote: Hi, I'm trying to plot a set of lines, 12 to be exact, and the default color cycle only supports 8 or 9 distinct colors. That said, I looked up the color maps and segmented it using 12 constant intervals with the hope of getting 12 distinct colors. The problem I'm running in to is that some of the line colors I get are too close to each other. This is because come shades in the colormap have a broader spectrum than others. Here is my code to set my custom default color cycle: import matplotlib as mpl cmap = mpl.cm.get_cmap(name='spectral') #I gues we can also use hsv or gist_rainbow nColors = 12 #number of colors incr = 0.9 / nColors self.mycolors = [] for i in np.arange(0,0.9,incr): self.mycolors.append(cmap(i)) you could replace the loop with a list comprehension: mycolors = [cmap(i) for i in np.arange(0,0.9,incr)] Also, arange may not be a great fit for this task; maybe linspace would work better: mycolors = [cmap(i) for i in np.linspace(0, 0.9, nColors)] This allows you to eliminate the assignment of `incr`. Note: the above colormap is different than that created by arange because linspace includes the endpoint, while arange doesn't. Hope that helps, -Tony mpl.axes.set_default_color_cycle(self.mycolors) Can anyone suggest a cleaner method? Or is there perhaps an existing class to provide distinct color lines? Thanks, Krishna -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] Basemap white space
2010/4/8 Filipe Fernandes ocef...@gmail.com:
BTW: What I meant by limitation is the fact that Agg has no GUI like the
nice QT window I was using before. The users of this script have no
experience with scripting languages and enjoyed choosing the format and
filename using a GUI interface.
I'm quite convinced that you can have the figure in multiple Canvases
at the same time. Or create the FigureCanvasAgg or the call to
.savefig() only on save time. In every widget framework, it should be
fairly easy to build a custom gui having a customised Save ...
button, I guess?
In addition, PIL's show() use an external linux program xv. In the end
I wanted to eliminate one external linux program (Imagemagik convert)
but ended up with another one...
When using Tkinter, you can use ImageTk:
im = {some PIL Image} # Some image to be shown
canvas = {some Tkinter.Canvas} # For drawing graphics
viewport = ImageTk.PhotoImage(im)
canvas.create_image((0, 0), image = viewport, anchor = 'nw') # Put
the image on the Tkinter.Canvas. Modify according your needs.
# Now the PIL Image has been rendered on the canvas.
# Maybe do canvas.update() or call the master's .update(),
# or call some .mainloop() entry function. For instance, use the
# Tkinter.Tk instance's method .mainloop().
When renewing the graphics, don't forget to canvas.delete({tag}) using
the {tag} returned by canvas.create_image(), otherwise you will
probably loose perfomance.
There are examples on matplotlib.sourceforge.net how to use Tkinter
with matplotlib.
hth,
Friedrich
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Re: [Matplotlib-users] custom color cycle from cmap
Thanks Tony. That helps clean up the code. Now that I think about it more, I actaually had 2 questions. The first you answered well. The second question relates to my problem when using this method in that it produces line colors where some colors are too similar. In other words, there isn't enough of a stark differnece in color between the lines. Can someone suggest a different method (or something that may already be built in) of coming up with 12 or more line colors (more than the built in 8) that are stark? (I know I'm nit-picking and can probably just pick out my own colors but it's an interesting excersize). -- View this message in context: http://old.nabble.com/custom-color-cycle-from-cmap-tp28177653p28180731.html Sent from the matplotlib - users mailing list archive at Nabble.com. -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
[Matplotlib-users] can't interact with embedded gtk
The following works without the --pylab switch but not with it. The error I get is some how related to a call to get the active figure which returns None. C:\Python26\lib\site-packages\mpl_toolkits\basemap\__init__.pyc in set_axes_limi ts(self, ax) 2531 if is_interactive(): 2532 figManager = _pylab_helpers.Gcf.get_active() - 2533 figManager.canvas.draw() AttributeError: 'NoneType' object has no attribute 'canvas'. In the following code. the error happens at m.drawcoastlines() Help? === from mpl_toolkits.basemap import Basemap, shiftgrid import numpy as np import matplotlib.pyplot as plt from matplotlib.backends.backend_gtkagg import \ FigureCanvasGTKAgg as FigureCanvas import gtk # create new figure #fig=plt.figure() from matplotlib.figure import Figure fig = Figure(figsize=(5,5), dpi=100) canvas = FigureCanvas(fig) window = gtk.Window(gtk.WINDOW_TOPLEVEL) window.add(canvas) # setup cylindrical equidistant map projection (global domain). ax = fig.add_axes([0.1,0.1,0.7,0.7]) m = Basemap(llcrnrlon=-180.,llcrnrlat=-90,urcrnrlon=180.,urcrnrlat=90.,\ resolution='c',area_thresh=1.,projection='cyl',ax=ax) m.drawcoastlines() m.tissot(-117,34,10,10) #plt.show() canvas.show() window.show() -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
[Matplotlib-users] 2 lines, 2 diff colors, when converged, gets 3rd color...
I'm plotting 2 lines with 2 colors. The lines are binary so they are somewhat square. When the lines converge on a same value for a period, their colors combine and turn into a 3rd color Is there a way to force the plotting to not blend the 2 colors together? I just want the 2nd line to lay on top of the 1st line. Any suggestions? -- View this message in context: http://old.nabble.com/2-lines%2C-2-diff-colors%2C-when-converged%2C-gets-3rd-color...-tp28182679p28182679.html Sent from the matplotlib - users mailing list archive at Nabble.com. -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] 2 lines, 2 diff colors, when converged, gets 3rd color...
The default behavior should be for the lines not to blend. Can you provide a short example script that illustrates what you're seeing? Or an image? Mike KrishnaPribadi wrote: I'm plotting 2 lines with 2 colors. The lines are binary so they are somewhat square. When the lines converge on a same value for a period, their colors combine and turn into a 3rd color Is there a way to force the plotting to not blend the 2 colors together? I just want the 2nd line to lay on top of the 1st line. Any suggestions? -- Michael Droettboom Science Software Branch Operations and Engineering Division Space Telescope Science Institute Operated by AURA for NASA -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] a quick way to plot 3D surface with point coordination?
Yes, Thanks, Friedrich. :-) This is exactly what I want. By now I know we have to plot over a uniformly sampled plane any way at the end of the day, no matter whether our original data is uniformly sampled or not. Zhe Yao On Thu, Apr 8, 2010 at 6:07 PM, Friedrich Romstedt friedrichromst...@gmail.com wrote: 2010/4/4 ericyosho ericyo...@gmail.com: Year, I think we could do unsorted scatter plot as well, however I'm still not satisfied with the book tracking routines I have to check when doing the surface plotting. What do you mean with book tracking routines? Anyway, maybe griddata would help you: http://matplotlib.sourceforge.net/api/mlab_api.html#matplotlib.mlab.griddata Friedrich -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
[Matplotlib-users] Colorbar shifting
Hello everyone, I'm working with hexbin() and I'd like the output to be shifted towards the red end of the spectrum. Does anyone know if there's a way to shift how the colors are output? Thanks! Rachel -- Download Intel#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
[Matplotlib-users] getting legend loc
Hi,
I'm having trouble getting some properties that are easily set :
leg=legend(loc=0)
is there a way to retrieve the legend location ?
In a similar vein :
axis('scaled')
is there a way to retrieve the scaled property ?
If no methods/properties are available in the default API is it
possible to implement them easily ?
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