.. index:: ! mgd77track
gmt mgd77track GEODAS-ids |SYN_OPT-R| |-J|parameters [ |-A|[c][size][+ispacing] ] [ |SYN_OPT-B| ] [ -Dastartdate ] [ |-D|bstopdate ] [ |-F| ] [ |-G|d|t|ngap ] [ |-I|a|c|m|t ] [ |-L|trackticks ] [ |-S|astartdist ] [ |-S|bstopdist ] [ |-T|T|t|dms,mc,mfs,mf,mfc ] [ |SYN_OPT-U| ] [ |SYN_OPT-V| ] [ |-W|[pen] ] [ |SYN_OPT-X| ] [ |SYN_OPT-Y| ] [ |SYN_OPT-p| ] [ |SYN_OPT-t| ] [ |SYN_OPT--| ]
mgd77track reads NCEI MGD77 cruises and plots one or more ship tracks on a map using the specified projection.
- -A[c][size][+ispacing]
- Append c to annotate the track using the MGD77 cruise ID [Default uses the filename prefix]. Optional size is the font size in points. The leg annotation font is controlled by :term:`FONT_LABEL`. By default, each leg is annotated every time it enters the map region. Alternatively, append +ispacing to place this label every spacing units apart along the track. Append one of the units k (km), n (nautical mile), d (day), or h (hour).
- -Dastartdate
- Do not plot data collected before startdate (yyyy-mm-ddT[hh:mm:ss]) [Default is first day].
- -Dbstopdate
- Do not plot data collected after stopdate (yyyy-mm-ddT[hh:mm:ss]). [Default is last day].
- -F
- Do not apply the error bit flags if present in a MGD77+ file [Default will apply these flags upon reading the data].
- -Gd|t|ngap
- Let successive point separations exceeding dgap (km) or tgap (minutes) indicate a break in the track where we should not draw a line [no gaps recognized]. Repeat to use both types of gap checking. The nN form is used to plot only one every other N points. This is useful to reduce plot file size bat cannot be used (will be ignored) with the other two gap types.
- -Ia|c|m|t
- Ignore certain data file formats from consideration. Append a|c|m|t to ignore MGD77 ASCII, MGD77+ netCDF, MGD77T ASCII, or plain table files, respectively. The option may be repeated to ignore more than one format. [Default ignores none].
- -Ltrackticks
- To put time/distance log-marks on the track. E.g. a500ka24ht6h means (a)nnotate every 500 km (k) and 24 h(ours), with (t)ickmarks every 500 km and 6 hours. Alternatively you may use the modifiers d (days) and n (nautical miles).
- -Sastartdist
- Do not plot data that are less than startdist meter along track from port of departure. Append k for km, M for miles, or n for nautical miles [Default is 0 meters].
- -Sbstopdist
- Do not plot data that are more than stopdist meter along track from port of departure. Append k for km, M for miles, or n for nautical miles [Default is end of track].
- -TT|t|dms,mc,mfs,mf,mfc
- Controls the attributes of the three kinds of markers (T for the first time marker in a new day, t for additional time markers in the same day, and d for distance markers). For each of these you can specify the 5 comma-separated attributes markersize, markercolor, markerfontsize, markerfont, and markerfontcolor. Repeat the |-T| option for each marker type.
- -W[pen]
- Append pen used for the trackline. [Defaults: width = 0.25p, color = black, style = solid].
To generate a Mercator map of the track of the cruise 01010007 in the area 70W to 20E, 40S to 20N, using a Mercator scale of 0.1inch/degree, label the tracks with 10 points characters, annotate the boundaries every 10 degrees, draw gridlines every 5 degrees, and mark the track every day and 1000 km, with ticks every 6 hours and 250 km, and create a PDF map, enter the following command:
gmt mgd77track 01010007 -R70W/20E/40S/20N -Jm0.1 -B10g5 -A10 \
-La1da1000kf6hf250k -pdf map
The Marine Geophysical Data Exchange Format - MGD77, see http://www.ngdc.noaa.gov/mgg/dat/geodas/docs/mgd77.txt
Wessel, P., and Chandler, M. T., 2007, The mgd77 supplement to the Generic Mapping Tools, Comp. Geosci., 33(1), 62-75, https://doi.org/10.1023/A:1021744224009.
:doc:`mgd77info`, :doc:`basemap </basemap>`, :doc:`mgd77list`