qgis - Using field calculator to delete specific contours

I have 3 contour shapefiles with 25m, 50m and 100m equidistance. Now I want to delete in the 25m-shp-file every **50m and **00m contour and in the 50m-shp-file every **00 contour. How can I show them using the field calculator of qgis?

Thanks!

Answer

If you have a contour value field, it should be possible to select **50m and **00m contours for later deletion using the following query with the modulo operator:

value % 50 = 0