Much easier is just to use the define axis/fromdata utility. Create a file with the depths you want: eg: lev.dat ----------- 25.0 81.25 156.25 275.0 462.5 712.5, 1175.0 2000.0 3000.0 4000.0 5500.0 ----------- Then the following will create a depth axis of these particular depths: file/var=depth lev.dat define axis/from/z/depth/name=gz depth