File Exchange Pick of the Week

January 21st, 2008

Practical Example: Generating points inside a polygon

Notice the link at the bottom for a one minute survey that can get you into a drawing for a MATLAB t-shirt!

This ten minute video shows how to modify the help example for INPOLYGON to generate a set number of points inside of a random polygon. The coding process is shown from beginning to end, with incremental testing, debugging and commentary on my though process.

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By Doug Hull

10:28 UTC | Posted in PodCast, Practical example, Video | Permalink | 5 Comments »

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5 Responses to “Practical Example: Generating points inside a polygon”

  1. Ryan Gray replied on January 24th, 2008 at 00:06 UTC :

    It seems there’s a problem again with your M4V conversion. Quicktime and iTunes say it’s MPEG-4 video, but they don’t think it has a video track and only play audio.

  2. Doug replied on January 24th, 2008 at 10:14 UTC :

    Ryan,

    Seems there was a slight change in file output since I wrote my MATLAB scripts that automate FTPing the files up to the server. Problem solved now. Thanks!

    Doug

  3. siv replied on September 12th, 2009 at 05:46 UTC :

    we have a data that contains long,lat and data values we have to plot a grid image using that data values how to get a grid image

    and we have to mask the grid image to india polygon

  4. Doug replied on September 14th, 2009 at 14:32 UTC :

    @sivi,

    You might want the mapping toolbox, dependent on what you are doing.

    I think you should send the details of what you are doing to:

    http://www.mathworks.com/support

    Doug

  5. Nathan replied on January 16th, 2010 at 06:26 UTC :

    Unfortunately this code has no runtime guarantees – I would avoid this algorithm for large numbers of random points.

    A more robust solution would involve triangulating the polygon and then picking a random point in a random triangle. Runtime is guaranteed to be linear in the number of points.

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