Provided by: gmt-common_5.4.3+dfsg-1_all bug


       grdclip - Clip the range of grids


       grdclip  ingrid   -Goutgrid  [   -Rregion  ]  [   -Sahigh/above  ]  [   -Sblow/below  ]  [
       -Silow/high/between ] [  -Srold/new ] [  -V[level] ]

       Note: No space is allowed between the option flag and the associated arguments.


       grdclip will set values < low to below and/or values > high to above. You can also specify
       one or more intervals where all values should be set to IT(between), or replace individual
       values.  Such operations are useful when you want all of a continent or an ocean  to  fall
       into  one  color  or  gray  shade  in image processing, when clipping of the range of data
       values is required, or for reclassification of data values.  above,  below,  between,  old
       and  new can be any number or even NaN (Not a Number). You must choose at least one of the
       -S options. Use -R to only extract a subset of the ingrid file.


       ingrid The input 2-D binary grid file.

              outgrid is the modified output grid file.


       -Rxmin/xmax/ymin/ymax[+r][+uunit] (more …)
              Specify the region of interest. Using the -R option will  select  a  subsection  of
              ingrid grid. If this subsection exceeds the boundaries of the grid, only the common
              region will be extracted.

              Set all data[i] > high to above.

              Set all data[i] < low to below.

              Set all data[i] >= low and <= high to between.   Repeat  the  option  for  as  many
              intervals as are needed.

              Set  all  data[i] == old to new.  This is mostly useful when your data are known to
              be integer values.  Repeat the option for as many replacements as are needed.

       -V[level] (more …)
              Select verbosity level [c].

       -^ or just -
              Print a short message about the syntax of the command, then exits (NOTE: on Windows
              just use -).

       -+ or just +
              Print  an  extensive  usage  (help)  message,  including  the  explanation  of  any
              module-specific option (but not the GMT common options), then exits.

       -? or no arguments
              Print a complete usage (help) message, including the explanation  of  all  options,
              then exits.


       By  default  GMT  writes  out grid as single precision floats in a COARDS-complaint netCDF
       file format. However, GMT is able to produce grid files in many other commonly  used  grid
       file formats and also facilitates so called “packing” of grids, writing out floating point
       data as 1- or 2-byte integers. (more …)


       To set all values > 70 to NaN and all values < 0 to 0 in file

              gmt grdclip -Sa70/NaN -Sb0/0 -V

       To reclassify all values in the 25-30 range to 99, those in 35-39 to 55, exchange  17  for
       11 and all values < 10 to 0 in file, try

              gmt grdclip -Si25/30/99 -Si35/39/55 -Sr17/11 -Sb10/0 -V


       gmt, grdlandmask, grdmask, grdmath, grd2xyz, xyz2grd


       2018, P. Wessel, W. H. F. Smith, R. Scharroo, J. Luis, and F. Wobbe