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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 additon to 22 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 Overview

   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 for a set of points

   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

   grdclip            Limit the z-range in gridded data sets

   grdcontour        Contouring of 2-D gridded data sets

   grdcut            Cut a sub-region from a grd file

   grdedit            Modify header information in a 2-D gridded file

   grdfft            Perform operations 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 sets

   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 sets 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 sets

   grdvolume        Volume calculations from 2-D gridded data sets

   makecpt            Make GMT color palette tables

   mapproject        Transformation of coordinate systems for 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 (Sun rasterfiles) 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) series

   trend2d            Fits polynomial trends to z = f(x,y) series

   triangulate        Perform optimal Delaunay triangulation and gridding

   xyz2grd            Convert an equidistant xyz file to a 2-D grd file

See Also

Look up the individual man pages for details. Information is also avaiable on the GMT World Wide Web home page


Wessel, P., and W. H. F. Smith, 1999, The Generic Mapping Tools (GMT) version 3.2 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,, Copyright 1995 by the 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.

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