GMT

GMT − The Generic Mapping Tools data processing and display software package

GMT is a collection of public-domain Unix tools that allows you to manipulate x,y and x,y,z data sets (filtering, trend fitting, gridding, projecting, etc.) and produce PostScript illustrations ranging from simple x-y plots, via contour maps, to artificially illuminated surfaces and 3-d perspective views in black/white or 24bit color. Linear, log10, and power scaling is supported in addition to 25 common map projections. The processing and display routines within GMT are completely general and will handle any (x,y) or (x,y,z) data as input.

GMT is also a wrapper script that can start any of the programs:

GMT module module-options

where module is the name of a GMT program and the options are those that pertain to that particular program.

The following is a summary of all the programs supplied with GMT and a very short description of their purpose. Detailed information about each program can be found in the separate manual pages.

blockmean L2 (x,y,z) data filter/decimator
blockmedian L1 (x,y,z) data filter/decimator
blockmode Mode (x,y,z) data filter/decimator
filter1d Filter 1-D data sets (time series)
fitcircle Finds the best-fitting great circle to a set of points
gmt2rgb Convert Sun rasterfile or grid to r, g, b grids
gmtconvert Convert between ASCII and binary 1-D tables
gmtdefaults List the current default settings
gmtmath Mathematical operations on data tables
gmtset Set individual default parameters
gmtselect Extract data subsets based on spatial criteria
grdfilter Filter 2-D data sets in the space domain
grd2cpt Make a color palette table from a grdfile
grd2xyz Conversion from 2-D gridded file to table data
grdblend Blend several partially over-lapping grdfiles onto one grid
grdclip Limit the z-range in gridded data
grdcontour Contouring of 2-D gridded data
grdcut Cut a sub-region from a grd file
grdedit Modify header information in a 2-D gridded file
grdfft Operate on grdfiles in the frequency domain
grdgradient Compute directional gradient from grdfiles
grdhisteq Histogram equalization for grdfiles
grdimage Produce images from 2-D gridded data
grdinfo Get information about grd files
grdlandmask Create mask grdfile from shoreline data base
grdmask Reset nodes outside a clip path to a constant
grdmath Mathematical operations on grdfiles
grdpaste Paste together grdfiles along a common edge
grdproject Project gridded data onto a new coordinate system
grdreformat Converting between different grdfile formats
grdsample Resample a 2-D gridded data set onto a new grid
grdtrend Fits polynomial trends to grdfiles
grdtrack Sampling of 2-D data set along 1-D track
grdvector Plot vector fields from grdfiles
grdview 3-D perspective imaging of 2-D gridded data
grdvolume Volume calculations from 2-D gridded data
makecpt Make GMT color palette tables
mapproject Forward or inverse map projections of table data
minmax Find extreme values in data tables
nearneighbor Nearest-neighbor gridding scheme
project Project data onto lines/great circles
psbasemap Create a basemap plot
psclip Use polygon files to define clipping paths
pscoast Plot coastlines and filled continents on maps
pscontour Contour xyz-data by triangulation
pshistogram Plot a histogram
psimage Plot images (EPS or Sun raster files) on maps
pslegend Plot legend on maps
psmask Create overlay to mask out regions on maps
psrose Plot sector or rose diagrams
psscale Plot grayscale or colorscale on maps
pstext Plot textstrings on maps
pswiggle Draw time-series along track on maps
psxy Plot symbols, polygons, and lines on maps
psxyz Plot symbols, polygons, and lines in 3-D
sample1d Resampling of 1-D table data sets
spectrum1d Compute various spectral estimates from time-series
splitxyz Split xyz-files into several segments
surface A continuous curvature gridding algorithm
trend1d Fits polynomial or Fourier trends to y = f(x) data
trend2d Fits polynomial trends to z = f(x,y) data
triangulate Perform optimal Delaunay triangulation and gridding
xyz2grd Convert equidistant xyz data to a 2-D grd file

Look up the individual man pages for details. By default, these pages are in $GMTHOME/man/manl, depending on your installation settings. Information is also available on the GMT home page gmt.soest.hawaii.edu or locally under $GMTHOME/www/gmt/gmt_services.html

Wessel, P., and W. H. F. Smith, 2005, The Generic Mapping Tools (GMT) version 4.1 Technical Reference & Cookbook, SOEST/NOAA.
Wessel, P., and W. H. F. Smith, 1998, New, Improved Version of Generic Mapping Tools Released, EOS Trans., AGU, 79 (47), p. 579.
Wessel, P., and W. H. F. Smith, 1995, New Version of the Generic Mapping Tools Released, EOS Trans., AGU, 76 (33), p. 329.
Wessel, P., and W. H. F. Smith, 1995, New Version of the Generic Mapping Tools Released, http: American Geophysical Union.
Wessel, P., and W. H. F. Smith, 1991, Free Software Helps Map and Display Data, EOS Trans., AGU, 72 (41), p. 441.