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ccrook / QGIS-Contour-Plugin

Contour plugin for QGIS - uses python matplotlib to generate contours of data on vector point data.
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Contour Plugin generated contours do not have enough nodes #21

Closed 63alfred closed 1 year ago

63alfred commented 6 years ago

I am using the contour plugin to generate intermediate contours. I have a vector file with 5 foot contours and want to interpolate 1 foot contours from it. The procedure I used was:

  1. Extract nodes from my 5 foot contours vector file. original-5-ft-contours nodes-from-original-5-ft-contours
  2. Create intermediate contours from nodes extracted from original 5 foot contours. intermediate-contours-from-contours-plugin
  3. Nodes from intermediate contours. nodes-of-intermediate-contours-from-contours-plugin

The problem is that the intermediate contours are not very good in some of the open areas. I assume that this is due to the nodes of the intermediate contours the open areas are too far apart.

Is there a way to get the contour plugin to generate more nodes in these open areas to make the generated intermediate contours in these open areas better?

ccrook commented 1 year ago

Closing stale issue.

The contour algorithm only contours on the data points it is provide with. Where there is no data it cannot know what the correct value is. You could use any of a number of other geospatial algorithm to interpolate into the areas where there is no data, and then contour the denser set of points. However there is no reason to suppose the interpolated data, or the resultant contours will be any more correct! They may look a little prettier though.