grdpaste man page

grdpaste — Join two grids along their common edge


grdpaste file_a.nc file_b.nc outfile.nc [ [level] ] [ -f<flags> ]

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


grdpaste will combine file_a.nc and file_b.nc into outfile.nc by pasting them together along their common edge. Files file_a.nc and file_b.nc must have the same dx, dy and have one edge in common. If in doubt, check with grdinfo and use grdcut and/or grdsample if necessary to prepare the edge joint. Note: For geographical grids, you may have to use -f to handle periodic longitudes unless the input grids are properly recognized as such via their meta-data.

Required Arguments

One of two files to be pasted together.
The other of two files to be pasted together.
The name for the combined output.

Optional Arguments

-V[level] (more ...)
Select verbosity level [c].
-f[i|o]colinfo (more ...)
Specify data types of input and/or output columns.
-^ or just -
Print a short message about the syntax of the command, then exits (NOTE: on Windows use just -).
-+ 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 options, then exits.
Print GMT version and exit.
Print full path to GMT share directory and exit.

Grid File Formats

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. To specify the precision, scale and offset, the user should add the suffix =id[/scale/offset[/nan]], where id is a two-letter identifier of the grid type and precision, and scale and offset are optional scale factor and offset to be applied to all grid values, and nan is the value used to indicate missing data. In case the two characters id is not provided, as in =/scale than a id=nf is assumed. When reading grids, the format is generally automatically recognized. If not, the same suffix can be added to input grid file names. See grdconvert and Section grid-file-format of the GMT Technical Reference and Cookbook for more information.

When reading a netCDF file that contains multiple grids, GMT will read, by default, the first 2-dimensional grid that can find in that file. To coax GMT into reading another multi-dimensional variable in the grid file, append ?varname to the file name, where varname is the name of the variable. Note that you may need to escape the special meaning of ? in your shell program by putting a backslash in front of it, or by placing the filename and suffix between quotes or double quotes. The ?varname suffix can also be used for output grids to specify a variable name different from the default: "z". See grdconvert and Sections modifiers-for-CF and grid-file-format of the GMT Technical Reference and Cookbook for more information, particularly on how to read splices of 3-, 4-, or 5-dimensional grids.


Suppose file_a.nc is 150E - 180E and 0 - 30N, and file_b.nc is 150E - 180E, -30S - 0, then you can make outfile.nc which will be 150 - 180 and -30S - 30N by:

gmt grdpaste file_a.nc file_b.nc -Goutfile.nc -V -fg

See Also

gmt, grdblend, grdclip, grdcut, grdinfo, grdsample


GMT 5.2.1 November 12, 2015