GRDCLIP

grdclip − Clipping of range in grdfiles.

grdclip input_file.grd −Goutput_file.grd [ −Sahigh/above ] [ −Sblow/below ] [ −V ]

grdclip will set values < low to below and/or values > high to above. Useful when you want all of a continent or an ocean to fall into one color or grayshade in image processing, or clipping of the range of data values is required. above/below can be any number or NaN (Not a Number). You must choose at least one of −Sa or −Sb.

input_file.grd

The input 2-D binary grdfile.

−G

output_file.grd is the modified output grdfile.

−Sa

Set all data[i] > high to above.

−Sb

Set all data[i] < low to below.

−V

Selects verbose mode, which will send progress reports to stderr [Default runs "silently"].

To set all values > 70 to NaN and all values < 0 to 0 in file data.grd:

grdclip data.grd −Gnew_data.grd −Sa70/NaN −Sb0/0 −V

GMT(l), grdlandmask(l), grdmask(l), grdmath(l), grd2xyz(l), xyz2grd(l)