#60 plcont draws more contour instead of one

closed-out-of-date
Alan W. Irwin
None
5
2014-08-21
2009-04-03
Big Muscle
No

Sometimes, plcont draws 2 contours where MATLab algorithm draws only one closed contour. Look at the attached image to see the problem. In the 3rd level, the MATLAB draws one (orange in picture) closed contour. But PLPlot draws two (violet and dark pink in picture) contours.

Is there something to do about it?
Thanks for the solution.

Discussion

  • Big Muscle
    Big Muscle
    2009-04-03

    Image showing the problem - same data where used on both contour plots.

     
    Attachments
  • Big Muscle
    Big Muscle
    2009-04-03

    I think it has something to do with "Extra logic is needed for squares where a contour passes through all four edges (saddle points) to determine which pairs of edges to connect." in MATLAB documentation, because plplot's "iedge" array (in pldrawcn) has set all elements to 1 for points which are incorrectly linked. This doesn't happen for other points.

    But I don't know how to treat it.

     
  • Alan W. Irwin
    Alan W. Irwin
    2009-11-16

    Could you please give simple example source code (in Python or C) to demonstrate this contour issue for PLplot? That would help us verify the issue.

     
  • Alan W. Irwin
    Alan W. Irwin
    2009-11-16

    • assigned_to: nobody --> airwin
     
  • Alan W. Irwin
    Alan W. Irwin
    2009-11-28

    We are attempting to process bugs in a more timely way now. bigmuscle appears to be out of contact (it's been 11 days since I posted the question for him) . We need his answer to this question to help us verify the bug. Therefore, I am closing this bug.

    bigmuscle, if you start monitoring your bug reports again, please answer the question here so I have a chance to verify the bug and follow up.

     
  • Alan W. Irwin
    Alan W. Irwin
    2009-11-28

    • status: open --> closed-out-of-date