# [SciPy-User] Obtaining contour data Classic List Threaded 5 messages Open this post in threaded view
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## [SciPy-User] Obtaining contour data

 Hello,         I have height data on a two  dimensional equidistant latitude longitude grid and my ultimate goal is to calculate the curvature of the contours. Here is an illustration of what I want to do - http://www.indiana.edu/%7Egeog109/topics/10_Forces&Winds/sfc_trough.html. The data is plotted on a two dimensional latitude longitude grid and then the height contours are calculated. I am looking to obtain the coordinates of the contours(shown in red) in terms of latitude and longitude so that I can use that information  to calculate the curvature of the contour points using a least squares method. Is it possible to do this in Scipy ? The curvature of the earth is itself irrelevant in this case and it can be assumed to be flat. Regards,Ashwin. _______________________________________________ SciPy-User mailing list [hidden email] https://mail.python.org/mailman/listinfo/scipy-user
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## Re: Obtaining contour data

 2017-10-16 15:31 GMT+02:00 ashwin .D :Hello,         I have height data on a two  dimensional equidistant latitude longitude grid and my ultimate goal is to calculate the curvature of the contours. Here is an illustration of what I want to do - http://www.indiana.edu/%7Egeog109/topics/10_Forces&Winds/sfc_trough.html. The data is plotted on a two dimensional latitude longitude grid and then the height contours are calculated. I am looking to obtain the coordinates of the contours(shown in red) in terms of latitude and longitude so that I can use that information  to calculate the curvature of the contour points using a least squares method. Is it possible to do this in Scipy ? The curvature of the earth is itself irrelevant in this case and it can be assumed to be flat. Regards,Ashwin. _______________________________________________ SciPy-User mailing list [hidden email] https://mail.python.org/mailman/listinfo/scipy-user _______________________________________________ SciPy-User mailing list [hidden email] https://mail.python.org/mailman/listinfo/scipy-user
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## Re: Obtaining contour data

 Yes I looked at that. The thing is my data is in raster coordinates(latitude and longitude - equidistant grid). When I pull out the coordinates from collections are these polygons (vectors) or is the raster  entity still retained ? On Mon, Oct 16, 2017 at 7:50 PM, Nicolas Cellier wrote:2017-10-16 15:31 GMT+02:00 ashwin .D :Hello,         I have height data on a two  dimensional equidistant latitude longitude grid and my ultimate goal is to calculate the curvature of the contours. Here is an illustration of what I want to do - http://www.indiana.edu/%7Egeog109/topics/10_Forces&Winds/sfc_trough.html. The data is plotted on a two dimensional latitude longitude grid and then the height contours are calculated. I am looking to obtain the coordinates of the contours(shown in red) in terms of latitude and longitude so that I can use that information  to calculate the curvature of the contour points using a least squares method. Is it possible to do this in Scipy ? The curvature of the earth is itself irrelevant in this case and it can be assumed to be flat. Regards,Ashwin. _______________________________________________ SciPy-User mailing list [hidden email] https://mail.python.org/mailman/listinfo/scipy-user _______________________________________________ SciPy-User mailing list [hidden email] https://mail.python.org/mailman/listinfo/scipy-user _______________________________________________ SciPy-User mailing list [hidden email] https://mail.python.org/mailman/listinfo/scipy-user
 If you fear that, you can easily map the raster coordinates to the real ones and convert this after extracting the contour. It's an extra step but should not be a real difficulty. Envoyé par TypeApp Le 16 oct. 2017, à 16:25, "ashwin .D" <[hidden email]> a écrit: Yes I looked at that. The thing is my data is in raster coordinates(latitude and longitude - equidistant grid). When I pull out the coordinates from collections are these polygons (vectors) or is the raster  entity still retained ? On Mon, Oct 16, 2017 at 7:50 PM, Nicolas Cellier wrote:2017-10-16 15:31 GMT+02:00 ashwin .D :Hello,         I have height data on a two  dimensional equidistant latitude longitude grid and my ultimate goal is to calculate the curvature of the contours. Here is an illustration of what I want to do - http://www.indiana.edu/%7Egeog109/topics/10_Forces&Winds/sfc_trough.html. The data is plotted on a two dimensional latitude longitude grid and then the height contours are calculated. I am looking to obtain the coordinates of the contours(shown in red) in terms of latitude and longitude so that I can use that information  to calculate the curvature of the contour points using a least squares method. Is it possible to do this in Scipy ? The curvature of the earth is itself irrelevant in this case and it can be assumed to be flat. Regards,Ashwin. _______________________________________________ SciPy-User mailing list [hidden email] https://mail.python.org/mailman/listinfo/scipy-user _______________________________________________ SciPy-User mailing list [hidden email] https://mail.python.org/mailman/listinfo/scipy-user `SciPy-User mailing list[hidden email]https://mail.python.org/mailman/listinfo/scipy-user`_______________________________________________ SciPy-User mailing list [hidden email] https://mail.python.org/mailman/listinfo/scipy-user