Re: [Matplotlib-users] contour's polygons
On 28 July 2010 01:31, Phil Rosenfield philr...@astro.washington.eduwrote: I'd like to use the polygons contour makes but I can't figure out how to get them from ContourSet. Any examples or links to helpful information would be excellent. Attached is an example of how to extract the polygons from a ContourSet. import matplotlib.pyplot as plt import numpy as np # Dummy x,y,z data. x = np.linspace(0, 1, 10) y = np.linspace(0, 1, 10) x,y = np.meshgrid(x,y) z = np.sin(7*x)*np.sin(7*y) # Contours levels. levels = [0, 0.4, 0.8] nlevels = len(levels) # Use either one of the following two lines: contourset = plt.contour(x, y, z, levels)# Line contours #contourset = plt.contourf(x, y, z, levels) # Filled contours # contourset.collections is a list of nlevels LineCollections if using contour # and a list of (nlevels-1) PathCollections if using contourf. print contourset.collections # Look at a single level index. If you want all of the contour levels, you # will need to loop through them. level = 1 print 'level is', levels[level] paths = contourset.collections[level].get_paths() npaths = len(paths) print 'number of paths', npaths for i in range(npaths): path = paths[i] print 'path', i, 'of', npaths # Each path has vertices, it may also have codes. If codes is None, the # vertices are a single continuous path of line segments and should be easy # to deal with. If codes is not None then vertices is probably 2 or more # discontinuous line segments; you will need to understand the codes for # MOVETO and LINETO at least - see lib/matplotlib/path.py for details. print ' codes', path.codes print ' vertices', path.vertices # Show the contour plot to help explanation. plt.colorbar() plt.show() -- The Palm PDK Hot Apps Program offers developers who use the Plug-In Development Kit to bring their C/C++ apps to Palm for a share of $1 Million in cash or HP Products. Visit us here for more details: http://p.sf.net/sfu/dev2dev-palm___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
[Matplotlib-users] contour's polygons
Hi, I'm 6 months into learning python and haven't been able to find a way to do this, so I hope you don't mind a basic question. I'd like to use the polygons contour makes but I can't figure out how to get them from ContourSet. Any examples or links to helpful information would be excellent. Thanks, Phil -- Phil Rosenfield Graduate Student: UW Astronomy Additional contact info: http://www.astro.washington.edu/philrose -- The Palm PDK Hot Apps Program offers developers who use the Plug-In Development Kit to bring their C/C++ apps to Palm for a share of $1 Million in cash or HP Products. Visit us here for more details: http://ad.doubleclick.net/clk;226879339;13503038;l? http://clk.atdmt.com/CRS/go/247765532/direct/01/ ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
Re: [Matplotlib-users] contour's polygons
On 07/27/2010 02:31 PM, Phil Rosenfield wrote: Hi, I'm 6 months into learning python and haven't been able to find a way to do this, so I hope you don't mind a basic question. I'd like to use the polygons contour makes but I can't figure out how to get them from ContourSet. Any examples or links to helpful information would be excellent. They are buried. Each contour set has a list of collections, and each of those collections has a set of paths, and each of those paths has a vertices attribute for its corresponding polygon. In the following we will pick out the first path of the first collection. cs = contour(rand(6,6)) c = cs.collections[0] p = c.get_paths()[0] v = p.vertices lev = cs.levels[0] The levels attribute is a list of levels corresponding to the list of collections: one collection per level. Eric Thanks, Phil -- The Palm PDK Hot Apps Program offers developers who use the Plug-In Development Kit to bring their C/C++ apps to Palm for a share of $1 Million in cash or HP Products. Visit us here for more details: http://p.sf.net/sfu/dev2dev-palm ___ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
