Julia wrapper for the Generic Mapping Tools GMT

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The Generic Mapping Tools, GMT, is an open source collection of tools for manipulating geographic and Cartesian data sets (including filtering, trend fitting, gridding, projecting, etc.) and producing PostScript illustrations ranging from simple x–y plots via contour maps to artificially illuminated surfaces and 3D perspective views. This link will take you to an impressive collection of figures made with GMT

This wrapper works with GMT6.4.0 and above and it is intended not only to access to GMT from within the Julia language but also to provide a more modern interface to the GMT modules. For example, instead of using the GMT classic syntax to do a line plot:

gmt psxy filename -R0/10/0/5 -JX12 -W1p -Ba -P >

one can simply do:

plot("filename", show=true)

or, more verbose but easier to read

coast(region=:global, proj=:Winkel, frame=:g, area=10000,
      land=:burlywood4, water=:wheat1, show=true)

instead of

gmt coast -Rd -JR12 -Bg -Dc -A10000 -Gburlywood4 -Swheat1 -P >

to show


] add GMT

A word about the installation. On Unix (Mac included) we now use a GMT_jll artifact to provide the GMT binary, but for Windows we keep using a MSVC GMT binary. This means that on Windows the GMT (the C lib) is not updated automatically (but GMT.jl is). Updates there are done manually by running upGMT(). Also, for some reasons it may be desirable to use a system wide GMT installation. To swap to a system wide GMT installation, do (in REPL):

  • import Pkg;"GMT")
  • restart Julia

Note the above will work up until some other reason triggers a Julia recompile, where the JLL artifacts will be used again. To make the ENV["SYSTEMWIDE_GMT"] = 1 solution permanent, declare a "SYSTEMWIDE_GMT" environment variable permanently in your .bashrc (or whatever).


The GMT Julia wrapper was designed to work in a way the close as possible to the command line version and yet to provide all the facilities of the Julia language. In this sense, all GMT options are put in a single text string that is passed, plus the data itself when it applies, to the gmt() command. However, we also acknowledge that not every one is comfortable with the GMT syntax. This syntax is needed to accommodate the immense pool of options that let you control all details of a figure but that also makes it harder to read/master.

To make life easier we provide also a new mechanism that use the GMT module name directly and where the program's options are set via keyword arguments. While the monolotic way of using this package is robust and keeps being updated to latestes GMT developments, this By modules alternative is a Work in Progress (several of the GMT supplements were not ported yet) and some things may not work yet. So all help is most than wellcome.

Documentation and Examples


A lot of the GDAL interface functions rely on code from GDAL.jl by Martijn Visser and ArchGDAL.jl by Yeesian Ng, released under the MIT license.


The GMT.jl is free software: you can redistribute it and/or modify it under the terms of the MIT "Expat" License. A copy of this license is provided in LICENSE.txt