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<title>MGD77TRACK</title>
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<h1 align=center>MGD77TRACK</h1>
<a href="#NAME">NAME</a><br>
<a href="#SYNOPSIS">SYNOPSIS</a><br>
<a href="#DESCRIPTION">DESCRIPTION</a><br>
<a href="#OPTIONS">OPTIONS</a><br>
<a href="#EXAMPLES">EXAMPLES</a><br>
<a href="#SEE ALSO">SEE ALSO</a><br>
<a href="#REFERENCES">REFERENCES</a><br>
<hr>
<a name="NAME"></a>
<h2>NAME</h2>
<p style="margin-left:11%; margin-top: 1em">mgd77track
− A shiptrack plotting program</p>
<a name="SYNOPSIS"></a>
<h2>SYNOPSIS</h2>
<p style="margin-left:11%; margin-top: 1em"><b>mgd77track</b>
<i>NGDC-ids</i>
<b>−R</b><i>west</i>/<i>east</i>/<i>south</i>/<i>north</i>[<b>r</b>]
<b>−J</b><i>parameters</i> [
<b>−A</b>[<b>c</b>][<i>size</i>][,<i>spacing</i>] ] [
<b>−B</b>[<b>p</b>|<b>s</b>]<i>parameters</i> ] [
<b>−C</b>|<b>g</b>|<b>e</b> ] [
<b>−Da</b><i>startdate</i> ] [
<b>−Db</b><i>stopdate</i> ] [ <b>−F</b> ] [
<b>−Gd</b>|<b>t</b><i>gap</i> ] [
<b>−I</b><i>ignore</i> ] [ <b>−K</b> ] [
<b>−L</b><i>trackticks</i> ] [ <b>−O</b> ] [
<b>−P</b> ] [
<b>−Sa</b><i>startdist</i>[<b>u</b>] ] [
<b>−Sb</b><i>stopdist</i>[<b>u</b>] ] [
<b>−TT</b>|<b>t</b>|<b>d</b><i>ms,mc,mfs,mf,mfc</i> ]
[
<b>−U</b>[<i>just</i>/<i>dx</i>/<i>dy</i>/][<b>c</b>|<i>label</i>]
] [ <b>−V</b> ] [ <b>−W</b><i>pen</i> ] [
<b>−X</b>[<b>a</b>|<b>c</b>|<b>r</b>][<i>x-shift</i>[<b>u</b>]]
] [
<b>−Y</b>[<b>a</b>|<b>c</b>|<b>r</b>][<i>y-shift</i>[<b>u</b>]]
] [ <b>−c</b><i>copies</i> ]</p>
<a name="DESCRIPTION"></a>
<h2>DESCRIPTION</h2>
<p style="margin-left:11%; margin-top: 1em"><b>mgd77track</b>
reads NGDC MGD77 cruises and creates <i>PostScript</i> code
that will plot one or more ship tracks on a map using the
specified projection. The <i>PostScript</i> code is written
to standard output. <i><br>
NGDC-ids</i></p>
<p style="margin-left:22%;">Can be one or more of five
kinds of specifiers: <br>
1) 8-character NGDC IDs, e.g., 01010083, JA010010etc., etc.
<br>
2) 2-character <agency> codes which will return all
cruises from each agency. <br>
3) 4-character <agency><vessel> codes, which
will return all cruises from those vessels. <br>
4) =<list>, where <list> is a table with NGDC
IDs, one per line. <br>
5) If nothing is specified we return all cruises in the data
base. <br>
(See mgd77info <b>−L</b> for agency and vessel codes).
The ".mgd77" or ".nc" extensions will
automatically be appended, if needed (use <b>−I</b> to
ignore certain file types). Cruise files will be looked for
first in the current directory and second in all directories
listed in <b>$MGD77_HOME</b>/mgd77_paths.txt [If
<b>$MGD77_HOME</b> is not set it will default to
<b>$GMT_SHAREDIR</b>/mgd77].</p>
<table width="100%" border=0 rules="none" frame="void"
cellspacing="0" cellpadding="0">
<tr valign="top" align="left">
<td width="11%"></td>
<td width="3%">
<p style="margin-top: 1em" valign="top"><b>−J</b></p> </td>
<td width="8%"></td>
<td width="78%">
<p style="margin-top: 1em" valign="top">Selects the map
projection. Scale is UNIT/degree, 1:xxxxx, or width in UNIT
(upper case modifier). UNIT is cm, inch, or m, depending on
the <b><A HREF="gmtdefaults.html#MEASURE_UNIT">MEASURE_UNIT</A></b> setting in .gmtdefaults4, but this
can be overridden on the command line by appending <b>c</b>,
<b>i</b>, or <b>m</b> to the scale/width value. When central
meridian is optional, default is center of longitude range
on <b>−R</b> option. Default standard parallel is the
equator. For map height, max dimension, or min dimension,
append <b>h</b>, <b>+</b>, or <b>-</b> to the width,
respectively.</p> </td>
</table>
<p style="margin-left:22%;">More details can be found in
the <b><A HREF="psbasemap.html">psbasemap</A></b> man pages.</p>
<p style="margin-left:22%; margin-top: 1em"><b>CYLINDRICAL
PROJECTIONS:</b></p>
<p style="margin-left:22%; margin-top: 1em"><b>−Jc</b><i>lon0/lat0/scale</i>
(Cassini) <b><br>
−Jcyl_stere</b>/[<i>lon0/</i>[<i>lat0/</i>]]<i>scale</i>
(Cylindrical Stereographic) <b><br>
−Jj</b>[<i>lon0/</i>]<i>scale</i> (Miller) <b><br>
−Jm</b>[<i>lon0</i>/[<i>lat0/</i>]]<i>scale</i>
(Mercator) <b><br>
−Jm</b><i>lon0/lat0/scale</i> (Mercator - Give
meridian and standard parallel) <b><br>
−Jo</b>[<b>a</b>]<i>lon0/lat0/azimuth/scale</i>
(Oblique Mercator - point and azimuth) <b><br>
−Jo</b>[<b>b</b>]<i>lon0/lat0/lon1/lat1/scale</i>
(Oblique Mercator - two points) <b><br>
−Joc</b><i>lon0/lat0/lonp/latp/scale</i> (Oblique
Mercator - point and pole) <b><br>
−Jq</b>[<i>lon0/</i>[<i>lat0/</i>]]<i>scale</i>
(Cylindrical Equidistant) <b><br>
−Jt</b><i>lon0/</i>[<i>lat0/</i>]<i>scale</i> (TM -
Transverse Mercator) <b><br>
−Ju</b><i>zone/scale</i> (UTM - Universal Transverse
Mercator) <b><br>
−Jy</b>[<i>lon0/</i>[<i>lat0/</i>]]<i>scale</i>
(Cylindrical Equal-Area)</p>
<p style="margin-left:22%; margin-top: 1em"><b>CONIC
PROJECTIONS:</b></p>
<p style="margin-left:22%; margin-top: 1em"><b>−Jb</b><i>lon0/lat0/lat1/lat2/scale</i>
(Albers) <b><br>
−Jd</b><i>lon0/lat0/lat1/lat2/scale</i> (Conic
Equidistant) <b><br>
−Jl</b><i>lon0/lat0/lat1/lat2/scale</i> (Lambert Conic
Conformal) <b><br>
−Jpoly</b>/[<i>lon0/</i>[<i>lat0/</i>]]<i>scale</i>
((American) Polyconic)</p>
<p style="margin-left:22%; margin-top: 1em"><b>AZIMUTHAL
PROJECTIONS:</b></p>
<p style="margin-left:22%; margin-top: 1em"><b>−Ja</b><i>lon0/lat0</i>[<i>/horizon</i>]<i>/scale</i>
(Lambert Azimuthal Equal-Area) <b><br>
−Je</b><i>lon0/lat0</i>[<i>/horizon</i>]<i>/scale</i>
(Azimuthal Equidistant) <b><br>
−Jf</b><i>lon0/lat0</i>[<i>/horizon</i>]<i>/scale</i>
(Gnomonic) <b><br>
−Jg</b><i>lon0/lat0</i>[<i>/horizon</i>]<i>/scale</i>
(Orthographic) <b><br>
−Jg</b><i>lon0/lat0/altitude/azimuth/tilt/twist/Width/Height/scale</i>
(General Perspective). <b><br>
−Js</b><i>lon0/lat0</i>[<i>/horizon</i>]<i>/scale</i>
(General Stereographic)</p>
<p style="margin-left:22%; margin-top: 1em"><b>MISCELLANEOUS
PROJECTIONS:</b></p>
<p style="margin-left:22%; margin-top: 1em"><b>−Jh</b>[<i>lon0/</i>]<i>scale</i>
(Hammer) <b><br>
−Ji</b>[<i>lon0/</i>]<i>scale</i> (Sinusoidal) <b><br>
−Jkf</b>[<i>lon0/</i>]<i>scale</i> (Eckert IV) <b><br>
−Jk</b>[<b>s</b>][<i>lon0/</i>]<i>scale</i> (Eckert
IV) <b><br>
−Jn</b>[<i>lon0/</i>]<i>scale</i> (Robinson) <b><br>
−Jr</b>[<i>lon0/</i>]<i>scale</i> (Winkel Tripel)
<b><br>
−Jv</b>[<i>lon0/</i>]<i>scale</i> (Van der Grinten)
<b><br>
−Jw</b>[<i>lon0/</i>]<i>scale</i> (Mollweide)</p>
<p style="margin-left:22%; margin-top: 1em"><b>NON-GEOGRAPHICAL
PROJECTIONS:</b></p>
<p style="margin-left:22%; margin-top: 1em"><b>−Jp</b>[<b>a</b>]<i>scale</i>[<i>/origin</i>][<b>r</b>|<b>z</b>]
(Polar coordinates (theta,r)) <b><br>
−Jx</b><i>x-scale</i>[<b>d</b>|<b>l</b>|<b>p</b><i>pow</i>|<b>t</b>|<b>T</b>][<i>/y-scale</i>[<b>d</b>|<b>l</b>|<b>p</b><i>pow</i>|<b>t</b>|<b>T</b>]]
(Linear, log, and power scaling)</p>
<table width="100%" border=0 rules="none" frame="void"
cellspacing="0" cellpadding="0">
<tr valign="top" align="left">
<td width="11%"></td>
<td width="3%">
<p style="margin-top: 1em" valign="top"><b>−R</b></p> </td>
<td width="8%"></td>
<td width="78%">
<p style="margin-top: 1em" valign="top"><i>west, east,
south,</i> and <i>north</i> specify the Region of interest,
and you may specify them in decimal degrees or in
[+-]dd:mm[:ss.xxx][W|E|S|N] format. Append <b>r</b> if lower
left and upper right map coordinates are given instead of
w/e/s/n. The two shorthands <b>−Rg</b> and
<b>−Rd</b> stand for global domain (0/360 and
-180/+180 in longitude respectively, with -90/+90 in
latitude). Alternatively, specify the name of an existing
grid file and the <b>−R</b> settings (and grid
spacing, if applicable) are copied from the grid.</p></td>
</table>
<a name="OPTIONS"></a>
<h2>OPTIONS</h2>
<p style="margin-left:11%; margin-top: 1em">No space
between the option flag and the associated arguments.</p>
<table width="100%" border=0 rules="none" frame="void"
cellspacing="0" cellpadding="0">
<tr valign="top" align="left">
<td width="11%"></td>
<td width="3%">
<p style="margin-top: 1em" valign="top"><b>−A</b></p> </td>
<td width="4%"></td>
<td width="82%">
<p style="margin-top: 1em" valign="top">Append <b>c</b> to
annotate using the MGD77 cruise ID [Default uses the
filename prefix]. Optional <i>size</i> is the font size in
points. The leg annotation font is controlled by
<b><A HREF="gmtdefaults.html#LABEL_FONT">LABEL_FONT</A></b>. By default, each leg is annotated every
time it enters the map region. Alternatively, append
,<i>spacing</i> to place this label every <i>spacing</i>
units apart along the track. Append one of the units
<b>k</b> (km), <b>n</b> (nautical mile), <b>d</b> (day), or
<b>h</b> (hour).</p></td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="3%">
<p style="margin-top: 1em" valign="top"><b>−B</b></p> </td>
<td width="4%"></td>
<td width="82%">
<p style="margin-top: 1em" valign="top">Sets map boundary
annotation and tickmark intervals; see the <b><A HREF="psbasemap.html">psbasemap</A></b>
man page for all the details.</p></td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="3%">
<p style="margin-top: 1em" valign="top"><b>−C</b></p> </td>
<td width="4%"></td>
<td width="82%">
<p style="margin-top: 1em" valign="top">Select procedure
for along-track distance calculation:</p></td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="3%"></td>
<td width="4%"></td>
<td width="82%">
<p valign="top"><b>f</b> Flat Earth distances.</p></td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="3%"></td>
<td width="4%"></td>
<td width="82%">
<p valign="top"><b>g</b> Great circle distances
[Default].</p> </td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="3%"></td>
<td width="4%"></td>
<td width="82%">
<p valign="top"><b>e</b> Geodesic distances on current GMT
ellipsoid.</p> </td>
</table>
<table width="100%" border=0 rules="none" frame="void"
cellspacing="0" cellpadding="0">
<tr valign="top" align="left">
<td width="11%"></td>
<td width="7%">
<p style="margin-top: 1em" valign="top"><b>−Da</b></p> </td>
<td width="4%"></td>
<td width="78%">
<p style="margin-top: 1em" valign="top">Do not plot data
collected before <i>startdate</i>
(yyyy-mm-dd<b>T</b>[hh:mm:ss]) [Default is first day].</p></td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="7%">
<p style="margin-top: 1em" valign="top"><b>−Db</b></p> </td>
<td width="4%"></td>
<td width="78%">
<p style="margin-top: 1em" valign="top">Do not plot data
collected after <i>stopdate</i>
(yyyy-mm-dd<b>T</b>[hh:mm:ss]). [Default is last day].</p></td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="7%">
<p style="margin-top: 1em" valign="top"><b>−F</b></p> </td>
<td width="4%"></td>
<td width="78%">
<p style="margin-top: 1em" valign="top">Do not apply the
error bit flags if present in a MGD77+ file [Default will
apply these flags upon reading the data].</p></td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="7%">
<p style="margin-top: 1em" valign="top"><b>−G</b></p> </td>
<td width="4%"></td>
<td width="78%">
<p style="margin-top: 1em" valign="top">Let successive
point separations exceeding <b>d</b><i>gap</i> (km) or
<b>t</b><i>gap</i> (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.</p></td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="7%">
<p style="margin-top: 1em" valign="top"><b>−I</b></p> </td>
<td width="4%"></td>
<td width="78%">
<p style="margin-top: 1em" valign="top">Ignore certain data
file formats from consideration. Append <b>a|c|t</b> to
ignore MGD77 ASCII, MGD77+ netCDF, or plain table files,
respectively. The option may be repeated to ignore more than
one format. [Default ignores none].</p></td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="7%">
<p style="margin-top: 1em" valign="top"><b>−K</b></p> </td>
<td width="4%"></td>
<td width="78%">
<p style="margin-top: 1em" valign="top">More
<i>PostScript</i> code will be appended later [Default
terminates the plot system].</p></td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="7%">
<p style="margin-top: 1em" valign="top"><b>−L</b></p> </td>
<td width="4%"></td>
<td width="78%">
<p style="margin-top: 1em" valign="top">To put
time/distance log-marks on the track. E.g.
<b>a</b>500<b>ka</b>24<b>ht</b>6<b>h</b> means
(<b>a</b>)nnotate every 500 km (<b>k</b>) and 24
<b>h</b>(ours), with (<b>t</b>)ickmarks every 500 km and 6
hours. Alternatively you may use the modifiers <b>d</b>
(days) and <b>n</b> (nautical miles).</p></td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="7%">
<p style="margin-top: 1em" valign="top"><b>−O</b></p> </td>
<td width="4%"></td>
<td width="78%">
<p style="margin-top: 1em" valign="top">Selects Overlay
plot mode [Default initializes a new plot system].</p></td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="7%">
<p style="margin-top: 1em" valign="top"><b>−P</b></p> </td>
<td width="4%"></td>
<td width="78%">
<p style="margin-top: 1em" valign="top">Selects Portrait
plotting mode [Default is Landscape, see <b><A HREF="gmtdefaults.html">gmtdefaults</A></b>
to change this].</p></td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="7%">
<p style="margin-top: 1em" valign="top"><b>−Sa</b></p> </td>
<td width="4%"></td>
<td width="78%">
<p style="margin-top: 1em" valign="top">Do not plot data
that are less than <i>startdist</i> meter along track from
port of departure. Append <b>k</b> for km, <b>m</b> for
miles, or <b>n</b> for nautical miles [Default is 0
meters].</p> </td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="7%">
<p style="margin-top: 1em" valign="top"><b>−Sb</b></p> </td>
<td width="4%"></td>
<td width="78%">
<p style="margin-top: 1em" valign="top">Do not plot data
that are more than <i>stopdist</i> meter along track from
port of departure. Append <b>k</b> for km, <b>m</b> for
miles, or <b>n</b> for nautical miles [Default is end of
track].</p> </td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="7%">
<p style="margin-top: 1em" valign="top"><b>−T</b></p> </td>
<td width="4%"></td>
<td width="78%">
<p style="margin-top: 1em" valign="top">Controls the
attributes of the three kinds of markers (<b>T</b> for the
first time marker in a new day, <b>t</b> for additional time
markers in the same day, and <b>d</b> for distance markers).
For each of these you can specify the 5 comma-separated
attributes <i>markersize</i>, <i>markercolor</i>,
<i>markerfontsize</i>, <i>markerfont</i>, and
<i>markerfontcolor</i>. Repeat the <b>−T</b> option
for each marker type.</p></td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="7%">
<p style="margin-top: 1em" valign="top"><b>−U</b></p> </td>
<td width="4%"></td>
<td width="78%">
<p style="margin-top: 1em" valign="top">Draw Unix System
time stamp on plot. By adding <i>just/dx/dy/</i>, the user
may specify the justification of the stamp and where the
stamp should fall on the page relative to lower left corner
of the plot. For example, BL/0/0 will align the lower left
corner of the time stamp with the lower left corner of the
plot. Optionally, append a <i>label</i>, or <b>c</b> (which
will plot the command string.). The <b><A HREF="GMT.html">GMT</A></b> parameters
<b><A HREF="gmtdefaults.html#UNIX_TIME">UNIX_TIME</A></b>, <b><A HREF="gmtdefaults.html#UNIX_TIME_POS">UNIX_TIME_POS</A></b>, and
<b><A HREF="gmtdefaults.html#UNIX_TIME_FORMAT">UNIX_TIME_FORMAT</A></b> can affect the appearance; see the
<b><A HREF="gmtdefaults.html">gmtdefaults</A></b> man page for details. The time string
will be in the locale set by the environment variable
<b>TZ</b> (generally local time).</p></td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="7%">
<p style="margin-top: 1em" valign="top"><b>−W</b></p> </td>
<td width="4%"></td>
<td width="78%">
<p style="margin-top: 1em" valign="top">Append <i>pen</i>
used for the trackline. [Default is 0.25p,black]. [Default
is solid].</p></td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="7%">
<p style="margin-top: 1em" valign="top"><b>−X
−Y</b></p> </td>
<td width="4%"></td>
<td width="78%">
<p style="margin-top: 1em" valign="top">Shift plot origin
relative to the current origin by (<i>x-shift,y-shift</i>)
and optionally append the length unit (<b>c</b>, <b>i</b>,
<b>m</b>, <b>p</b>). You can prepend <b>a</b> to shift the
origin back to the original position after plotting, or
prepend <b>r</b> [Default] to reset the current origin to
the new location. If <b>−O</b> is used then the
default (<i>x-shift,y-shift</i>) is (0,0), otherwise it is
(r1i, r1i) or (r2.5c, r2.5c). Alternatively, give <b>c</b>
to align the center coordinate (x or y) of the plot with the
center of the page based on current page size.</p></td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="7%">
<p style="margin-top: 1em" valign="top"><b>−V</b></p> </td>
<td width="4%"></td>
<td width="78%">
<p style="margin-top: 1em" valign="top">Selects verbose
mode, which will send progress reports to stderr [Default
runs "silently"].</p></td>
<tr valign="top" align="left">
<td width="11%"></td>
<td width="7%">
<p style="margin-top: 1em" valign="top"><b>−c</b></p> </td>
<td width="4%"></td>
<td width="78%">
<p style="margin-top: 1em" valign="top">Specifies the
number of plot copies. [Default is 1].</p></td>
</table>
<a name="EXAMPLES"></a>
<h2>EXAMPLES</h2>
<p style="margin-left:11%; margin-top: 1em">To generate a
Mercator plot 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 send the plot to
the default printer, enter the following command:</p>
<p style="margin-left:11%; margin-top: 1em"><b>mgd77track</b>
01010007 <b>−R</b>70W/20E/40S/20N <b>−Jm</b>0.1
<b>−B</b>10<b>g</b>5 <b>−A</b>10
<b>−L</b>a1da1000kf6hf250k | lpr</p>
<a name="SEE ALSO"></a>
<h2>SEE ALSO</h2>
<p style="margin-left:11%; margin-top: 1em"><i><A HREF="mgd77info.html">mgd77info</A></i>(1),
<i><A HREF="psbasemap.html">psbasemap</A></i>(1) <i><A HREF="mgd77list.html">mgd77list</A></i>(1)</p>
<a name="REFERENCES"></a>
<h2>REFERENCES</h2>
<p style="margin-left:11%; margin-top: 1em">Wessel, P., and
W. H. F. Smith, 2009, The Generic Mapping Tools (GMT)
version 4.5.0 Technical Reference & Cookbook,
SOEST/NOAA. <br>
Wessel, P., and W. H. F. Smith, 1998, New, Improved Version
of Generic Mapping Tools Released, EOS Trans., AGU, 79 (47),
p. 579. <br>
Wessel, P., and W. H. F. Smith, 1995, New Version of the
Generic Mapping Tools Released, EOS Trans., AGU, 76 (33), p.
329. <br>
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. <br>
Wessel, P., and W. H. F. Smith, 1991, Free Software Helps
Map and Display Data, EOS Trans., AGU, 72 (41), p. 441. <br>
The Marine Geophysical Data Exchange Format -
"MGD77", see
<i>http://www.ngdc.noaa.gov/mgg/dat/geodas/docs/mgd77.txt</i></p>
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