I have an error in QGIS that I cannot seem to figure out. I have a zip-code level shapefile from the U.S. Census. I'm merging that with a data file by zip of counts. I want to make a dot density shapefile using the Random Points ftool. However I get a pesky error message as follows:
"Too many features couldn't be calculated due to conversion error. Please check out message log for more infor"
I've seen the underlying Python code where this error message is created, but I can't seem to find the source. The message log shows the following
2016-03-21T23:50:23 0 QGIS Ready! 2016-03-22T00:05:17 1 WARNING - fTools: Random Points 2016-03-22T00:05:17 1 The following feature ids should be checked. 2016-03-22T00:05:17 1 Feature id: 33143 2016-03-22T00:05:17 1 Feature id: 33143 .... .... 2016-03-22T00:20:04 1 End of features to be checked.
There are many lines in between the dot continuations. So First off, I'm not sure how to check the Feature referenced, as I'm not sure what that feature is. Without knowing something about the source of the error, I'm not sure how to proceed.
A couple of thoughts. The number of points crammed into a zipcode can be as high as 493. I doubt having too many points in a polygon can create that, but just throwing it out there. Second, most zipcodes are null values. Third, the original Census zipcode polygons were clipped to exclude water along the ocean coasts and the great lakes. Other than that I'm at a loss.