The Generic Mapping Tools (GMT) could not have been designed without the generous support of several people. We gratefully acknowledge A. B. Watts and the late W. F. Haxby for supporting our efforts on the original version 1.0 while we were their graduate students at Lamont-Doherty Earth Observatory. Doug Shearer and Roger Davis patiently answered many of our questions over e-mail. The subroutine gauss used in grdtrend was written and supplied by Bill Menke, L-DEO. Further development of versions 2.0 and 2.1 at SOEST would not have been possible without the support from the Hawaii Institute of Geophysics and School of Ocean and Earth Science and Technology Post-Doctoral Fellowship program to Paul Wessel. Walter H. F. Smith gratefully acknowledges the generous support of the C. H. and I. M. Green Foundation for Earth Sciences at the Institute of Geophysics and Planetary Physics, Scripps Institution of Oceanography, University of California at San Diego. GMT versions 3.0-3.4, 4.0-4.3.0 owe their existence to grants EAR-93-02272, OCE-95-29431, OCE-00-82552, and OCE-04-52126 from the National Science Foundation, which we gratefully acknowledge.
We would also like to acknowledge the feedback we have received from many of the users of earlier versions. Many of these suggestions have been implemented, and the bug reports have been useful in providing more robust programs. Specifically, we would like to thank Michael Barck, Manfred Brands, Stephan Eickschen, Ben Horner-Johnson, John Kuhn, Angel Li, John Lillibridge, Joaquim Luis, Andrew Macrae, Alex Madon, Greg Neumann, Lloyd Parkes, Ameet Raval, Remko Scharroo, Georg Schwarz, Richard Signell, Dirk Stoecker, Mikhail Tchernychev, Malte Thoma, David Townsend, William Weibel, and many others for advice on how to make GMT portable to DEC, SGI, HP, IBM, Apple and NEXT workstations, and to Windows PCs. Allen Cogbill provided OS/2 patches for EMX; John Lillibridge provided the original example 11; Hanno von Lom helped resolve early problems with DLL libraries for Win32; Jaoquim Luis created the ps2raster program; Lloyd Parkes enabled indexed color images in PostScript; Remko Scharroo implemented the PostScript image compression techniques, the interface for COARDS-compliant netCDF grids, and provided the nc2xy program; Kurt Schwehr maintains the Fink packages; Wayne Wilson implemented the full general perspective projection; and William Yip helped translate GMT to POSIX ANSI C and incorporate netCDF 3. The SOEST RCF staff (Ross Ishida, Pat Townsend, and Sharon Stahl) provided valuable help on Linux, web, and CGI script issues.