On 2006-05-24, Robert Kern <[EMAIL PROTECTED]> wrote: > Yes, unfortunately, much of the documentation was written by people who were > very familiar with the Matlab interfaces that these functions are emulating.
Since I've never used matlab, I'm a bit clueless. >> For example one parameter is specied as "an array". No clue as >> to how many dimensions or what the axis are. >> >> In another place it says "the X,Y parameters specify the (x,y) >> coordinates of a surface". _How_ do they specify the surface? >> Are they just equal length lists of x and y coordinates that >> specify len(X) points. Or do they specify a len(X) x len(Y) >> grid of points? > >> Why would my Z values be a 2D array? > > contour() only does contouring on gridded data. That's what I was beginning to suspect. What confused me was that if it required gridded data, I expected the input parameters to specify a grid (e.g. for a 5x7 grid, the X parameter would be a vector of 5 values, and the Y parameter would be a vector of 7 values) rather than just lie on a grid. > If you want to handle scattered datapoints, you will have to > do some interpolation. > > http://www.scipy.org/Cookbook/Matplotlib/Gridding_irregularly_spaced_data Thanks, that looks like exactly what I need. My next step was actually going to be to use the Delaunay triangulation module to interpolate the data onto a much finer grid. > So X, Y, and Z are all 2-D arrays laid out corresponding to > the grid that you have sampled. I thought the contour_demo.py > example was reasonably clear on this, but if you didn't get it > to run, then I can see why you wouldn't have read it. I did delete some code that was attempting to label the graph, and then it ran. The examples do use gridded data, but when I changed them to non-gridded data, it seemed to run fine. > Talking about this on matplotlib-users will probably get these > problems fixed faster: > > https://lists.sourceforge.net/lists/listinfo/matplotlib-users After I got the demos to run, it became apparent that the contour functions don't do what I want anyway, so it's all moot at this point. -- Grant Edwards grante Yow! YOW!! Now I at understand advanced visi.com MICROBIOLOGY and th' new TAX REFORM laws!! -- http://mail.python.org/mailman/listinfo/python-list