mgd77togmt(1gmt) [debian man page]
MDG77TOGMT(1gmt) Generic Mapping Tools MDG77TOGMT(1gmt) NAME
mgd77togmt - Convert an MGD-77 ASCII file to a binary gmt file SYNOPSIS
mgd77togmt [ -Llist ] [ mgd77file ] -Flegid -Ystart_year [ -Ainformation ] [ -Itime_increment ] [-T[<offset>]] [-W[<cable_length>]] [ -V ] DESCRIPTION
mgd77togmt reads an ASCII MGD-77 format file [or standard input] and creates a binary gmt file. The 16 header records specified in the MGD-77 documentation may or may not be present. If two-way travel times are available, mgd77togmt will convert those to corrected depths using the Carter tables. Both old and new (Y2K-compliant) MGD-77 files are supported. -L Name of file with several records of the format mgd77file legid start_year. For multiple files, use this option rather than the -F -Y combination. -Y The year of the first data point in the file. If not provided and -L option not used, it tries to get it from a header file. The header file must be in the same directory of the main file and must have a name equal to the main but with a .h77 extension. OPTIONS
No space between the option flag and the associated arguments. -A Set an optional 10 character information string to be stored in the header [Default is blank]. -F Leg id that will be used in file name (legid.gmt). If not given, it will be constructed from the mgd77file name plus the .gmt exten- sion. -I Used for files where time is missing. The increment is used to calculate fake times. -T Extracts Total field instead of anomaly. Since F does not hold in a 2 byte signed variable we subtract a constant [default = 40000] but you can provide another value in <offset>. -W Take into account that the magnetometer is not at ship's position. <cable> is magnetometer tow distance [default = 200 meters]. If -W only is given (e.g. no <cable>) and like with the -Y option, we try to get the tow distance from the header file. Failing, defaults to 200 meters. Note that this option will throw away the first points whose accumulated. distance since the start of mag- netic acquisition is less than cable. length, and likewise for the end of the mag profile. -V Selects verbose mode, which will send progress reports to stderr [Default runs "silently"]. EXAMPLES
To create a gmt file from the ASCII file c2104.mgd77, run mgd77togmt c2104.mgd77 -Y1977 To create new gmt files from all the mgd77 files listed in list.d: mgd77togmt -Llist.d -V SEE ALSO
dat2gmt(1), GMT(1) REFERENCES
Wessel, P., and W. H. F. Smith, 2011, The Generic Mapping Tools (GMT) version 4.5.7 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://www.agu.org/eos_elec/95154e.html, 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. MGD77 Task Group, 1977, The Marine Geophysical Data Exchange Format - MGD77, Key to Geophysical Records documentation No. 10, National Geo- physical and Solar-Terrestrial Data Center, Boulder, CO. Carter, D. J. T., Echo Sounding Correction Tables: Formerly Matthews' Tables, 150 pp, Hydrographic Department, Ministry of Defense, Taunton, Somerset, England, 1980. GMT 4.5.7 15 Jul 2011 MDG77TOGMT(1gmt)
Check Out this Related Man Page
GMT(l) GMT(l) NAME
gmt - The Generic Mapping Tools data processing and display software package INTRODUCTION
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 sur- faces and 3-d perspective views in black/white or 24bit color. Linear, log10, and power scaling is supported in additon 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. SYNOPSIS
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. GMT OVERVIEW
The following is a summary of all the programs supplied with GMT and a very short description of their purpose. Detailed informa- tion 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 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 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 (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) 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 SEE ALSO
Look up the individual man pages for details. These pages are in /usr/share/man/man1/*.1gmt.gz on a Debian system. Information is also available on the GMT home page gmt.soest.hawaii.edu or locally under /usr/share/doc/gmt-doc/gmt_services.html if the gmt-doc package is installed. REFERENCES
Wessel, P., and W. H. F. Smith, 2001, The Generic Mapping Tools (GMT) version 3.4 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. 1 Jan 2004 GMT(l)