I'm working with 2 different sets of contour lines and I want to subtract one from the other and make a new contour map from that. It seems simple. I have two set of lines with an elevation attribute and wherever they cross is a point that contains the difference in that elevation. Then, I create a contour map from those points. Is there a way to do this with some kind of function because manually placing points takes too long? I've tried the raster calculator but my data is not in a raster format. Any help is appreciated.