[Matplotlib-users] irregular grid of points: how to set figure pixel dimension ?
Hi all, I want to plot an irregular grid of points with x coordinates that can assume values between 0 and 13216 and y coordinates that can assume values between 0 and 8985 on a transparent canvas and save it as a .png file. I use Agg backend. I would like than to superimpose the obtained .png image over another image (not obtained with matplotlib and not with python) of 13217 x 8986 pixels. This because the irregular grid points of the first image are pixels of the second image. I have write this script where samples = 13217 lines = 8986 dpi = 100 xvect and yvect 2 numpy vectors that i have to convert to lists. # data aspect ratio data_aspect_ratio = samples / float(lines) # figure axis inches dimension x_axis_inches = lines / float(dpi) y_axis_inches = data_aspect_ratio * x_axis_inches # drawing figure canvas figure_label = p.figure(facecolor = 'w', edgecolor = 'w', figsize=(x_axis_inches, y_axis_inches), frameon = False) # main axes enlarging to fill all vanvas main_axes = p.axes([0, 0, 1, 1]) # plot grid points_1 = p.plot(xvect.tolist(), yvect.tolist(), 'D') # grid setting properties p.setp(points_1, markersize = 30, markeredgecolor = 'b', markerfacecolor = 'None', markeredgewidth = 7) main_axes.axis([0, lines, 0, samples]) # transparence main_axes.axesPatch.set_alpha(0.0) # deleting asix ticks p.setp(main_axes, xticks = [], yticks = []) # reversing y axis y_reversing = main_axes.set_ylim(main_axes.get_ylim()[::-1]) # image saving p.savefig(out_image_file, dpi = dpi) # closing figure p.close(figure_label) The problem is that i obtain a .png image of 13216 x 8985 pixels and not of 13217 x 8986 pixels as i planned. What can it be the problem ? Thank you all. -- -- Emanuele Passera - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
[Matplotlib-users] pcolor and masked arrays; am I missing something?
Howdy, I'm a recent refugee from GMT (Generic Mapping Tools) and am very happy to have found matplotlib. I've been having one nagging issue however that I must resolve as I require this ability. Basically, I need to mask 2d arrays and plot the result with pcolor via basemap. From the documentation it seems this should be fairly straight forward and I'm hoping that this is the case. Here is an example of problem. --- from pylab import * import matplotlib.numerix.ma as ma # matplotlibrc has numerix : numpy from matplotlib.toolkits.basemap import Basemap, shiftgrid, addcyclic import numpy as N . . . im = 144 jm = 93 lons = N.array([0., ... 357.5],dtype=float) lats = N.array([-90., ... 90.],dtype=float) topo_screen = N.zeros((jm,im),dtype='float') topo_screen[10] = 1 new_test = 100.*N.ones((jm,im),dtype='float') masked_test = ma.masked_where(topo_screen,new) This works and a screen dump of masked_test seem correct. A call to pcolor however results in the following: matplotlib version 0.90.1 verbose.level helpful interactive is False units is True platform is linux2 numerix numpy 1.0.1 . . . /usr/local/lib/python2.5/site-packages/numpy/core/ma.py:604: UserWarning: Cannot automatically convert masked array to numeric because data is masked in one or more locations. --- Is this an embarrassingly simple error on my part? I hope so. Any help would be much appreciated. Mike - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] pcolor and masked arrays; am I missing something?
Mike, pcolor has had masked array support for a long time. Please send a minimal but complete example of a script that fails; based on what you sent below, I can't tell what the problem is. Eric Mike Bauer wrote: Howdy, I'm a recent refugee from GMT (Generic Mapping Tools) and am very happy to have found matplotlib. I've been having one nagging issue however that I must resolve as I require this ability. Basically, I need to mask 2d arrays and plot the result with pcolor via basemap. From the documentation it seems this should be fairly straight forward and I'm hoping that this is the case. Here is an example of problem. --- from pylab import * import matplotlib.numerix.ma http://matplotlib.numerix.ma as ma # matplotlibrc has numerix : numpy from matplotlib.toolkits.basemap import Basemap, shiftgrid, addcyclic import numpy as N . . . im = 144 jm = 93 lons = N.array([0., ... 357.5],dtype=float) lats = N.array([-90., ... 90.],dtype=float) topo_screen = N.zeros((jm,im),dtype='float') topo_screen[10] = 1 new_test = 100.* N.ones((jm,im),dtype='float') masked_test = ma.masked_where(topo_screen,new) This works and a screen dump of masked_test seem correct. A call to pcolor however results in the following: matplotlib version 0.90.1 verbose.level helpful interactive is False units is True platform is linux2 numerix numpy 1.0.1 . . . /usr/local/lib/python2.5/site-packages/numpy/core/ma.py:604: UserWarning: Cannot automatically convert masked array to numeric because data is masked in one or more locations. --- Is this an embarrassingly simple error on my part? I hope so. Any help would be much appreciated. Mike - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
[Matplotlib-users] histogram question
I need to generate a set of histograms, but would like to plot only the skyline of the histogram, and leave out the vertical lines where adjencent bars touch. I have looked at the docs, but nothing jumped out at me as the right keyword for this. Is this possible? and if so, how? Cheers Tommy - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] histogram question
On Sep 24, 2007, at 2:32 PM, Tommy Grav wrote: I need to generate a set of histograms, but would like to plot only the skyline of the histogram, and leave out the vertical lines where adjencent bars touch. I have looked at the docs, but nothing jumped out at me as the right keyword for this. Is this possible? and if so, how? I believe that you can do the same thing using the regular plot command with linestyles='steps' (but I think you need to fiddle with the x values so that the steps are aligned properly. But it would be nice if hist could do this too. Perry - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] histogram question
I wrote the following code to do this for me...it is not entirely general (in the sense that it doesn't accept all kwargs beyond bins and hatch) and also allows me to do my own normalization But you should be able to use it pretty easily. def open_hist(arr,bins=10,norm=None,hatch=None): import matplotlib as mpl import pylab # Get all of the scaling right by allowing pylab to do it. d = pylab.hist(arr,bins) ax = pylab.gca() for i in d[2]: ax.patches.remove(i) width = d[1][1]-d[1][0] if norm is None: norm = 1. else: norm = float(norm) # Determine the vertices of the no-line histogram. verts = [] for i in range(len(d[0])): if i==0: x = d[1][i] y = 0. verts.append((x,y)) if i==len(d[0])-1: x = d[1][i] y = d[0][i]/norm verts.append((x,y)) x = d[1][i]+width verts.append((x,y)) y = 0. verts.append((x,y)) else: x = d[1][i] y = d[0][i]/norm verts.append((x,y)) x = d[1][i]+width verts.append((x,y)) # Let pylab do its thing p = pylab.Polygon(verts,transform=ax.transData,hatch=hatch) p.set_fill(0) ax.add_patch(p) On Mon, 24 Sep 2007, Tommy Grav wrote: I need to generate a set of histograms, but would like to plot only the skyline of the histogram, and leave out the vertical lines where adjencent bars touch. I have looked at the docs, but nothing jumped out at me as the right keyword for this. Is this possible? and if so, how? Cheers Tommy - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] histogram question
Perry Greenfield wrote: On Sep 24, 2007, at 2:32 PM, Tommy Grav wrote: I need to generate a set of histograms, but would like to plot only the skyline of the histogram, and leave out the vertical lines where adjencent bars touch. I have looked at the docs, but nothing jumped out at me as the right keyword for this. Is this possible? and if so, how? I believe that you can do the same thing using the regular plot command with linestyles='steps' (but I think you need to fiddle with the x values so that the steps are aligned properly. But it would be nice if hist could do this too. There is also an axes step() method in svn. Eric - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
[Matplotlib-users] pcolor and masked arrays; am I missing something?
Howdy, I'm a recent refugee from GMT (Generic Mapping Tools) and am very happy to have found matplotlib. I've been having one nagging issue however that I must resolve as I require this ability. Basically, I need to mask 2d arrays and plot the result with pcolor via basemap. From the documentation it seems this should be fairly straight forward and I'm hoping that this is the case. Here is an example of problem. --- from pylab import * import matplotlib.numerix.ma as ma # matplotlibrc has numerix : numpy from matplotlib.toolkits.basemap import Basemap, shiftgrid, addcyclic import numpy as N . . . im = 144 jm = 93 lons = N.array([0., ... 357.5],dtype=float) lats = N.array([-90., ... 90.],dtype=float) topo_screen = N.zeros((jm,im),dtype='float') topo_screen[10] = 1 new_test = 100.*N.ones((jm,im),dtype='float') masked_test = ma.masked_where(topo_screen,new) This works and a screen dump of masked_test seem correct. A call to pcolor however results in the following: matplotlib version 0.90.1 verbose.level helpful interactive is False units is True platform is linux2 numerix numpy 1.0.1 . . . /usr/local/lib/python2.5/site-packages/numpy/core/ma.py:604: UserWarning: Cannot automatically convert masked array to numeric because data is masked in one or more locations. --- Is this an embarrassingly simple error on my part? I hope so. Any help would be much appreciated. Mike - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
[Matplotlib-users] error on build on windows from SVN
I'm having problems building matplotlib on windows from a folder from SVN, and haven't done it before (previously had used the prebuilt binary download). I don't know what I am doing wrong. I'm on winXP, Python 2.5. and will be using wxPython 2.8.4.2 with matplotlib as well. The folder with the contents from SVN I've named matplotlib_svn. From the cmd line and while in that directory I wrote python setup.py build and got what follows. I'm not sure what I am to do (regarding finding an appropriate compiler). Any help is appreciated. C:\Python25\Lib\site-packages\matplotlib_svnpython setup.py build BUILDING MATPLOTLIB matplotlib: 0.90.1 python: 2.5 (r25:51908, Sep 19 2006, 09:52:17) [MSC v.1310 32 bit (Intel)] platform: win32 Windows version: (5, 1, 2600, 2, 'Service Pack 2') REQUIRED DEPENDENCIES numpy: 1.0 freetype2: found, but unknown version (no pkg-config) * WARNING: Could not find 'freetype2' headers in any * of '.', '.\freetype2'. OPTIONAL DEPENDENCIES Gtk+: no * Building for Gtk+ requires pygtk; you must be able * to import gtk in your build/install environment Tkinter: Tkinter: 50704, Tk: 8.4, Tcl: 8.4 * Tkinter present, but header files are not * installed. You may need to install development * packages. wxPython: 2.8.4.2 * WxAgg extension not required for wxPython = 2.8 Qt: no Qt4: no Cairo: no libpng: found, but unknown version (no pkg-config) * Could not find 'libpng' headers in any of '.' [Edit setup.cfg to suppress the above messages] running build running build_py copying lib\matplotlib\mpl-data\matplotlibrc - build\lib.win32- 2.5\matplotlib\m pl-data running build_ext No module named msvccompiler in numpy.distutils, trying from distutils.. error: Python was built with Visual Studio 2003; extensions must be built with a compiler than can generate compatible binaries. Visual Studio 2003 was not found on this system. If you have Cygwin installed, you can try compiling with MingW32, by passing -c mingw32 to setup.py. - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] error on build on windows from SVN
On 9/24/07, C M [EMAIL PROTECTED] wrote: I'm having problems building matplotlib on windows from a folder from SVN, and haven't done it before (previously had used the prebuilt binary download). I don't know what I am doing wrong. Read the header of setupext.py, particularly the part for win32 users -- it may not be totally current, but will get much you closer to your goal. Once you have followed the steps there, if you hit another roadblock check back here and we will advise further and try and update the docs as necessary. You are actually in the best position to write documentation, since you are hitting this for the first time, so please take notes and/or update the instructions in setupext.py so we can add them to the docs. Thanks, JDH - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
[Matplotlib-users] error on build on windows from SVN
On 9/24/07, John Hunter [EMAIL PROTECTED] wrote: On 9/24/07, C M [EMAIL PROTECTED] wrote: I'm having problems building matplotlib on windows from a folder from SVN, and haven't done it before (previously had used the prebuilt binary download). I don't know what I am doing wrong. Read the header of setupext.py, particularly the part for win32 users -- it may not be totally current, but will get much you closer to your goal. Once you have followed the steps there, if you hit another roadblock check back here and we will advise further and try and update the docs as necessary. You are actually in the best position to write documentation, since you are hitting this for the first time, so please take notes and/or update the instructions in setupext.py so we can add them to the docs. Well, not familiar with this at all but giving it a try...In the setupext.py header it reads: This build is similar to the mingw. Download the visual studio static dependencies from http://matplotlib.sourceforge.net/win32_static_vs.tar.gz and see the README in that dir I did that. Then, README there says: Contents: Static dependencies for building mpl for win32 using Visual Studio. Extract to the matplotlib source folder. I extracted it to the matplotlib folder itself and also on another try the subfolder, src. In both cases then from cmd did: python setup.py build bdist_wininst In both cases got same error as before. I like to be more help but I am not sure what to do. It isn't crucial that I get the latest via SVN and build it myself, but I thought it would be good to learn to do this generally, just didn't realize it would be a bit of an expedition. Not sure what to do. Thanks. - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
[Matplotlib-users] etframes: Applying the ideas of Edward Tufte to matplotlib
I came across this piece by Adam Hupp on programming.reddit.com just now. It looks interesting: http://hupp.org/adam/weblog/2007/09/03/etframes-applying-the-ideas-of-edward-tufte-to-matplotlib/ - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
