Calculate elevations based on existing elevations

Discussion created by sunrenchen on Feb 1, 2013
Hi all,

Actually, I have a feature which represents contour lines who has a field 'Elevations'. This field is not fully populated which means only some contour lines have elevations. The other contour lines have values of 'NULL'. What I want to do is to calculate these 'NULL' elevations based on the existing elevations with an interval of 1. That is, say we have two known contour lines whose elevations are 450 and 455, there are four contour lines between these two lines. I want to assign them with the values of 451,452,453,454. How can I do that?