Cutting grids with similar extents
I have data layers in two grids: one environmental variable and one species presence data. I want to overlay the two grids, but in order to do this both grids must have the same resolution and extent. The resolution is the same in both grids. However, the extents are very slightly different from each other.
Min X: 12.083333 Min Y: 48.541667 Columns: 813 Rows: 301
Max X: 18.858333 Max Y: 51.05
Min X: 12.08586 Min Y: 48.540841 Columns: 813 Rows: 302
Max X: 18.86086 Max Y: 51.057508
I have tried using the cut function in DIVA GIS, copying the extent of one gridfile to change the other, and then inputting the largest minimum values and smallest maximum values from the two grids. I have tried exporting the grids as ASCII files and then editing the minimum x and y values (in the ASCII header) in Notepad, but this is not suitable as it causes a translation (spatial shift) in the data.
Any suggestions of how I can get the extent of these 2 grids to match? Or is this an unsolvable problem - if the extents of 2 grids are too similar, can DIVA GIS not distinguish between them and cut them to match?
Nigel Taylor, UK