Provided by: gmt_6.0.0+dfsg-1build2_amd64 bug

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 surfaces and 3-D perspective views in
       black/white or full color. Linear, log10, and power scaling is supported in addition to  over  30  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 the main program that can start any of the modules:

       gmt module module-options
              Starts a given GMT module with the module-options that pertain to that particular module.   A  few
              special commands are also available:

       gmt clear items
              Deletes  current  defaults,  or  the cache, data or sessions directories.  Choose between defaults
              (deletes the current gmt.conf file used for the current modern session), cache (deletes the user’s
              cache  directory and all of its content), data (deletes the user’s data download directory and all
              of its content), or all (does all of the above).

       gmt begin [session-prefix] [format] [options]
              Initializes a new GMT session under modern mode [Default is classic mode].  All work is  performed
              in  a  temporary  work  directory.  The optional session-prefix assigns a name to the session, and
              this may be used as figure name for single-figure sessions [gmtsession].  Likewise,  the  optional
              format can be used to override the default graphics format [PDF].

       gmt figure prefix [format(s)] [options]
              Specifies  the  desired  name,  output format(s) and any custom arguments that should be passed to
              psconvert when producing this figure.  All subsequent plotting will be directed  to  this  current
              figure  until  another  gmt  figure  command is issued or the session ends.  The prefix is used to
              build final figure names when extensions are automatically  appended.  The  format  setting  is  a
              comma-separated list of desired extensions (e.g., pdf,png).

       gmt inset [arguments]
              Allows  users  to  place a map inset by temporarily changing where plotting takes place as well as
              the region and projection, then resets to previous stage.

       gmt subplot [arguments]
              Allows users to create a matrix of panels with automatic labeling and advancement.

       gmt end [show]
              Terminates a GMT modern mode session and automatically converts the registered illustration(s)  to
              the  specified  formats,  then eliminates the temporary work directory.  The figures are placed in
              the current directory.

       If no module is given then several other options are available:

       --help List and description of GMT modules.

       --new-script[=L]
              Write a GMT modern mode script  template  to  stdout.  Optionally  append  the  desired  scripting
              language  among  bash,  csh,  or  batch.   Default is the main shell closest to your current shell
              (e.g., bash for zsh, csh for tcsh).

       --show-bindir
              Show directory of executables and exit.

       --show-citation
              Show the citation for the latest GMT publication.

       --show-cores
              Show number of available cores.

       --show-datadir
              Show data directory/ies and exit.

       --show-dataserver
              Show URL of the remote GMT data server.

       --show-doi
              Show the DOI of the current release.

       --show-modules
              List module names on stdout and exit.

       --show-library
              Show the path of the shared GMT library.

       --show-plugindir
              Show plugin directory and exit.

       --show-sharedir
              Show share directory and exit.

       --version
              Print version and exit.

       =      Check if that module exist and if so the program will exit with status of 0; otherwise the  status
              of exit will be non-zero.

COMMAND-LINE COMPLETION

       GMT  provides  basic  command-line completion (tab completion) for bash.  The completion rules are either
       installed in /etc/bash_completion.d/gmt or <prefix>/share/tools/gmt_completion.bash.   Depending  on  the
       distribution,  you may still need to source the gmt completion file from ~/.bash_completion or ~/.bashrc.
       For more information see Section command-line-completion in the CookBook.

GMT MODULES

       Run gmt --help to print the list of all core and supplementals modules  within  GMT,  and  a  very  short
       description  of  their  purpose.   Detailed  information  about each program can be found in the separate
       manual pages.

CUSTOM MODULES

       The gmt program can also load custom modules from shared libraries built as  specified  in  the  GMT  API
       documentation.   This way your modules can benefit form the GMT infrastructure and extend GMT in specific
       ways.

THE COMMON GMT OPTIONS

        -B[p|s]parameters -Jparameters -Jz|Zparameters -K -O
        -Rwest/east/south/north[/zmin/zmax][+r][+uunit]
        -U[stamp]
        -V[level]
        -X[a|c|f|r][xshift[u]]
        -Y[a|c|f|r][yshift[u]] -aflags -bbinary -dnodata -eregexp -fflags -ggaps -hheaders -iflags  -jflags  -n‐
       flags -oflags -pflags -rreg -sflags -ttransp -x[[-]n] -:[i|o]

DESCRIPTION

       These  are  all  the  common  GMT options that remain the same for all GMT programs. No space between the
       option flag and the associated arguments.

       -B[p|s]parameters
              Set map Frame and Axes parameters. The Frame parameters are specified by

              -B[axes][+b][+gfill][+n][+olon/lat][+ttitle]

              where axes selects which axes to plot. By default, all 4 map boundaries (or plot axes) are plotted
              (named  W,  E,  S,  N).  To customize, append the codes for those you want (e.g., WSn). Upper case
              means plot and annotate while lower case just plots and ticks the specified axes.  To just draw an
              axis  without annotation and ticks you can use the l(eft), r(ight), b(ottom), t(opt) and (for 3-D)
              u(p) codes. If a 3-D basemap is selected with -p and -Jz,  append  Z,  z,  or  u  to  control  the
              appearance  of  the  vertical  axis. By default a single vertical axes will be plotted at the most
              suitable map corner. Override the default by appending any combination of corner ids 1234, where 1
              represents  the  lower  left  corner  and  the order goes counter-clockwise. Append +b to draw the
              outline of the 3-D cube defined by -R; this modifier is also needed to display  gridlines  in  the
              x-z,  y-z  planes.  Note that for 3-D views the title, if given, will be suppressed. You can paint
              the interior of the canvas with +gfill.  Append +n  to  have  no  frame  and  annotations  at  all
              [Default  is  controlled  by  the codes].  Optionally append +oplon/plat to draw oblique gridlines
              about specified pole [regular gridlines]. Ignored if  gridlines  are  not  requested  (below)  and
              disallowed  for the oblique Mercator projection.  To add a plot title (+ttitle). The Frame setting
              is optional but can be invoked once to override the above defaults.

              The Axes parameters are specified by

              -B[p|s][x|y|z]intervals[+aangle|n|p][+l|Llabel][+pprefix][+uunit]

              but you may also split this into two separate invocations for clarity, i.e.,

       • -B[p|s][x|y|z][+aangle|n|p][+l|Llabel][+pprefix][+s|Sseclabel][+uunit]

       • -B[p|s][x|y|z]intervals

         The first optional flag following -B selects p (rimary) [Default]  or  s  (econdary)  axes  information
         (mostly  used  for  time  axes  annotations).   The  [x|y|z] flags specify which axes you are providing
         information for.  If none are given then we default to xy.  If you wish to  give  different  annotation
         intervals  or  labels  for  the  various axes then you must repeat the B option for each axis (If a 3-D
         basemap is selected with -p and -Jz, use -Bz to give settings for the vertical axis.).  To add a  label
         to  an  axis,  just append +llabel (Cartesian projections only). Use +L to force a horizontal label for
         y-axes (useful for very short labels).  For Cartesian axes you may specify an alternate via +s which is
         used for right or upper axis axis label (with any +l label used for left and bottom axes).  If the axis
         annotation should have a leading text prefix (e.g., dollar sign for those plots of your net worth)  you
         can  append  +pprefix.  For  geographic  maps  the  addition  of degree symbols, etc. is automatic (and
         controlled by the GMT default setting FORMAT_GEO_MAP). However, for other plots you  can  add  specific
         units  by  adding  +uunit.   If any of these text strings contain spaces or special characters you will
         need to enclose them in quotes.  Cartesian x-axes also allow for the optional +aangle, which will  plot
         slanted  annotations;  angle is measured with respect to the horizontal and must be in the -90 <= angle
         <= 90 range only.  Also, +an is a shorthand for normal (i.e., +a90) and +ap for  parallel  (i.e.,  +a0)
         annotations  [Default].   For  the  y-axis,  arbitrary  angles  are not allowed but +an and +ap specify
         annotations normal [Default] and parallel to the axis, respectively.  Note that these defaults  can  be
         changed via MAP_ANNOT_ORTHO.

         The intervals specification is a concatenated string made up of substrings of the form

         [a|f|g]stride[+|-phase][u].

         The  leading  a  is  used  to specify the annotation and major tick spacing [Default], f for minor tick
         spacing, and g for gridline spacing. stride is the desired stride interval. The optional  phase  shifts
         the  annotation interval by that amount (positive or negative). The optional unit indicates the unit of
         the stride and can be any of the ones listed below:

         • Y (year, plot with 4 digits)

         • y (year, plot with 2 digits)

         • O (month, plot using FORMAT_DATE_MAP)

         • o (month, plot with 2 digits)

         • U (ISO week, plot using FORMAT_DATE_MAP)

         • u (ISO week, plot using 2 digits)

         • r (Gregorian week, 7-day stride from start of week TIME_WEEK_START)

         • K (ISO weekday, plot name of weekdays in selected language)

         • k (weekday, plot number of day in the week (1–7) (see TIME_WEEK_START))

         • D (date, plot using FORMAT_DATE_MAP)

         • d (day, plot day of month 0-31 or year 1-366, via FORMAT_DATE_MAP)

         • R (day, same as d, aligned with TIME_WEEK_START)

         • H (hour, plot using FORMAT_CLOCK_MAP)

         • h (hour, plot with 2 digits)

         • M (minute, plot using FORMAT_CLOCK_MAP)

         • m (minute, plot with 2 digits)

         • S (second, plot using FORMAT_CLOCK_MAP)

         • s (second, plot with 2 digits).

         Note for geographic axes m and s instead mean arc minutes and  arc  seconds.   All  entities  that  are
         language-specific  are  under  control  by  GMT_LANGUAGE.  Alternatively,  for linear maps, we can omit
         stride, thus setting xinfo, yinfo,  or  zinfo  to  a  plots  annotations  at  automatically  determined
         intervals,

         • ag plots both annotations and grid lines with the same spacing,

         • afg adds suitable minor tick intervals,

         • g plots grid lines with the same interval as if -Bf was used.

         For  custom  annotations  and intervals, let intervals be given as cintfile, where intfile contains any
         number of records with coord type [label]. Here, type is one or more letters from a|i, f,  and  g.  For
         a|i  you  must  supply  a  label  that  will  be  plotted  at the coord location.  For non-geographical
         projections: Give negative scale (in -Jx) or axis length (in -JX) to change the direction of increasing
         coordinates  (i.e., to make the y-axis positive down).  For log10 axes: Annotations can be specified in
         one of three ways:

         1. stride can be 1, 2, 3, or -n. Annotations will then occur at 1, 1-2-5, or 1-2-3-4-…-9, respectively;
            for  -n  we  annotate  every  n’t  magnitude.  This  option  can also be used for the frame and grid
            intervals.

         2. An l is appended to the tickinfo string. Then, log10 of the tick value is plotted at  every  integer
            log10 value.

         3. A  p  is appended to the tickinfo string. Then, annotations appear as 10 raised to log10 of the tick
            value.

         For power axes: Annotations can be specified in one of two ways:

         1. stride sets the regular annotation interval.

         2. A p is appended to the tickinfo  string.  Then,  the  annotation  interval  is  expected  to  be  in
            transformed  units, but the annotation value will be plotted as untransformed units. E.g., if stride
            = 1 and power = 0.5 (i.e., sqrt), then equidistant annotations labeled 1-4-9…  will appear.

         Finally, if your axis is in radians you can use multiples or fractions of pi  to  set  such  annotation
         intervals.  The format is [n]pi[m], for an optional integer n and optional m fractions 2, 3, or 4.

         These   GMT   parameters   can   affect  the  appearance  of  the  map  boundary:  MAP_ANNOT_MIN_ANGLE,
         MAP_ANNOT_MIN_SPACING,     FONT_ANNOT_PRIMARY,     FONT_ANNOT_SECONDARY,      MAP_ANNOT_OFFSET_PRIMARY,
         MAP_ANNOT_OFFSET_SECONDARY,    MAP_ANNOT_ORTHO,    MAP_FRAME_AXES,   MAP_DEFAULT_PEN,   MAP_FRAME_TYPE,
         FORMAT_GEO_MAP,  MAP_FRAME_PEN,  MAP_FRAME_WIDTH,  MAP_GRID_CROSS_SIZE_PRIMARY,   MAP_GRID_PEN_PRIMARY,
         MAP_GRID_CROSS_SIZE_SECONDARY,    MAP_GRID_PEN_SECONDARY,    FONT_TITLE,   FONT_LABEL,   MAP_LINE_STEP,
         MAP_ANNOT_OBLIQUE,         FORMAT_CLOCK_MAP,         FORMAT_DATE_MAP,          FORMAT_TIME_PRIMARY_MAP,
         FORMAT_TIME_SECONDARY_MAP,      GMT_LANGUAGE,     TIME_WEEK_START,     MAP_TICK_LENGTH_PRIMARY,     and
         MAP_TICK_PEN_PRIMARY; see the gmt.conf man page for details.

       -Jparameters

       Select map projection. The following character determines the projection. If the character is upper  case
       then  the argument(s) supplied as scale(s) is interpreted to be the map width (or axis lengths), else the
       scale argument(s) is the map scale (see its definition for each projection). UNIT is cm, inch, or  point,
       depending  on the PROJ_LENGTH_UNIT setting in gmt.conf, but this can be overridden on the command line by
       appending c, i, or p to the scale or width values. Append +dh, +du, or +dl to  the  given  width  if  you
       instead  want  to  set  map  height,  the  maximum  (upper)  dimension, or the minimum (lower) dimension,
       respectively [Default is +dw for width].  In case the central meridian is an optional parameter and it is
       being  omitted,  then  the  center  of  the  longitude  range given by the -R option is used. The default
       standard parallel is the equator.  The ellipsoid used in the map projections is user-definable by editing
       the  gmt.conf  file  in  your  home  directory.  73  commonly used ellipsoids and spheroids are currently
       supported, and users may also specify their own custom ellipsoid parameters [Default is WGS-84].  Several
       GMT  parameters  can  affect  the  projection:  PROJ_ELLIPSOID,  GMT_INTERPOLANT,  PROJ_SCALE_FACTOR, and
       PROJ_LENGTH_UNIT; see the gmt.conf man page for details.  Choose one of the following projections (The  E
       or C after projection names stands for Equal-Area and Conformal, respectively):
          CYLINDRICAL PROJECTIONS:
          -Jclon0/lat0/scale or -JClon0/lat0/width (Cassini).
              Give projection center lon0/lat0 and scale (1:xxxx or UNIT/degree).
          -Jcyl_stere/[lon0/[lat0/]]scale or -JCyl_stere/[lon0/[lat0/]]width (Cylindrical Stereographic).
              Give central meridian lon0 (optional), standard parallel lat0 (optional), and scale along parallel
              (1:xxxx or UNIT/degree). The standard parallel is typically one of these (but can be any value):

                 • 66.159467 - Miller’s modified Gall

                 • 55 - Kamenetskiy’s First

                 • 45 - Gall’s Stereographic

                 • 30 - Bolshoi Sovietskii Atlas Mira or Kamenetskiy’s Second

                 • 0 - Braun’s Cylindrical
          -Jj[lon0/]scale or -JJ[lon0/]width (Miller Cylindrical Projection).
              Give the central meridian lon0 (optional) and scale (1:xxxx or UNIT/degree).
          -Jm[lon0/[lat0/]]scale or -JM[lon0/[lat0/]]width (Mercator [C])
              Give central meridian lon0 (optional), standard parallel lat0 (optional), and scale along parallel
              (1:xxxx or UNIT/degree).
          -Joparameters (Oblique Mercator [C]).
              Typically used with -RLLx/LLy/URx/URyr or with projected coordinates.  Specify one of:

              -Jo[a|A]lon0/lat0/azimuth/scale or -JO[a|A]lon0/lat0/azimuth/width
                     Set projection center lon0/lat0, azimuth of oblique equator, and scale.

              -Jo[b|B]lon0/lat0/lon1/lat1/scale or -JO[b|B]lon0/lat0/lon1/lat1/scale
                     Set projection center lon0/lat0, another point on the oblique equator lon1/lat1, and scale.

              -Joc|Clon0/lat0/lonp/latp/scale or -JOc|Clon0/lat0/lonp/latp/scale
                     Set  projection  center  lon0/lat0,  pole of oblique projection lonp/latp, and scale.  Give
                     scale along oblique equator (1:xxxx  or  UNIT/degree).   Use  upper-case  A|B|C  to  remove
                     enforcement of a northern hemisphere pole.
          -Jq[lon0/[lat0/]]scale or -JQ[lon0/[lat0/]]width (Cylindrical Equidistant).
              Give the central meridian lon0 (optional), standard parallel lat0 (optional), and scale (1:xxxx or
              UNIT/degree). The standard parallel is typically one of these (but can be any value):

                 • 61.7 - Grafarend and Niermann, minimum linear distortion

                 • 50.5 - Ronald Miller Equirectangular

                 • 43.5 - Ronald Miller, minimum continental distortion

                 • 42 - Grafarend and Niermann

                 • 37.5 - Ronald Miller, minimum overall distortion

                 • 0 - Plate Carree, Simple Cylindrical, Plain/Plane Chart
          -Jtlon0/[lat0/]scale or -JTlon0/[lat0/]width (Transverse Mercator [C])
              Give  the  central  meridian  lon0,  central  parallel  lat0  (optional),  and  scale  (1:xxxx  or
              UNIT/degree).
          -Juzone/scale or -JUzone/width (UTM - Universal Transverse Mercator [C]).
              Give  the  UTM  zone  (A,B,1-60[C-X],Y,Z))  and  scale (1:xxxx or UNIT/degree).  Zones: If C-X not
              given, prepend - or + to enforce southern or northern hemisphere conventions [northern if south  >
              0].
          -Jy[lon0/[lat0/]]scale or -JY[lon0/[lat0/]]width (Cylindrical Equal-Area [E]).
              Give the central meridian lon0 (optional), standard parallel lat0 (optional), and scale (1:xxxx or
              UNIT/degree). The standard parallel is typically one of these (but can be any value):

                 • 50 - Balthasart

                 • 45 - Gall

                 • 37.0666 - Caster

                 • 37.4 - Trystan Edwards

                 • 37.5 - Hobo-Dyer

                 • 30 - Behrman

                 • 0 - Lambert (default)

          CONIC PROJECTIONS:

          -Jblon0/lat0/lat1/lat2/scale or -JBlon0/lat0/lat1/lat2/width (Albers [E]).
                 Give projection center lon0/lat0, two  standard  parallels  lat1/lat2,  and  scale  (1:xxxx  or
                 UNIT/degree).

          -Jdlon0/lat0/lat1/lat2/scale or -JDlon0/lat0/lat1/lat2/width (Conic Equidistant)
                 Give  projection  center  lon0/lat0,  two  standard  parallels  lat1/lat2, and scale (1:xxxx or
                 UNIT/degree).

          -Jllon0/lat0/lat1/lat2/scale or -JLlon0/lat0/lat1/lat2/width (Lambert [C])
                 Give origin lon0/lat0, two standard parallels lat1/lat2,  and  scale  along  these  (1:xxxx  or
                 UNIT/degree).

          -Jpoly/[lon0/[lat0/]]scale or -JPoly/[lon0/[lat0/]]width ((American) Polyconic).
                 Give  the  central  meridian  lon0  (optional),  reference  parallel  lat0 (optional, default =
                 equator), and scale along central meridian (1:xxxx or UNIT/degree).

          AZIMUTHAL PROJECTIONS:

          Except for polar aspects, -Rw/e/s/n will be reset to -Rg.  Use -R<…>r for smaller regions.

          -Jalon0/lat0[/horizon]/scale or -JAlon0/lat0[/horizon]/width (Lambert [E]).
                 lon0/lat0 specifies the projection center. horizon specifies the max distance  from  projection
                 center  (in  degrees,  <= 180, default 90). Give scale as 1:xxxx or radius/lat, where radius is
                 distance in UNIT from origin to the oblique latitude lat.

          -Jelon0/lat0[/horizon]/scale or -JElon0/lat0[/horizon]/width (Azimuthal Equidistant).
                 lon0/lat0 specifies the projection center. horizon specifies the max distance  from  projection
                 center  (in  degrees, <= 180, default 180). Give scale as 1:xxxx or radius/lat, where radius is
                 distance in UNIT from origin to the oblique latitude lat.

          -Jflon0/lat0[/horizon]/scale or -JFlon0/lat0[/horizon]/width (Gnomonic).
                 lon0/lat0 specifies the projection center. horizon specifies the max distance  from  projection
                 center  (in  degrees,  <  90,  default 60). Give scale as 1:xxxx or radius/lat, where radius is
                 distance in UNIT from origin to the oblique latitude lat.

          -Jglon0/lat0[/horizon]/scale or -JGlon0/lat0[/horizon]/width (Orthographic).
                 lon0/lat0 specifies the projection center. horizon specifies the max distance  from  projection
                 center  (in  degrees,  <=  90, default 90). Give scale as 1:xxxx or radius/lat, where radius is
                 distance in UNIT from origin to the oblique latitude lat.

          -Jglon0/lat0/altitude/azimuth/tilt/twist/Width/Height/scale                                         or
          -JGlon0/lat0/altitude/azimuth/tilt/twist/Width/Height/width (General Perspective).
                 lon0/lat0  specifies  the  projection  center.  altitude is the height (in km) of the viewpoint
                 above local sea level. If altitude is less than 10, then it is the distance from the center  of
                 the  earth  to  the  viewpoint in earth radii. If altitude has a suffix r then it is the radius
                 from the center of the earth in kilometers. azimuth is measured to the east of north  of  view.
                 tilt  is the upward tilt of the plane of projection. If tilt is negative, then the viewpoint is
                 centered on the horizon. Further, specify  the  clockwise  twist,  Width,  and  Height  of  the
                 viewpoint in degrees. Give scale as 1:xxxx or radius/lat, where radius is distance in UNIT from
                 origin to the oblique latitude lat.

          -Jslon0/lat0[/horizon]/scale or -JSlon0/lat0[/horizon]/width (General Stereographic [C]).
                 lon0/lat0 specifies the projection center. horizon specifies the max distance  from  projection
                 center  (in  degrees,  <  180,  default 90). Give scale as 1:xxxx (true at pole) or lat0/1:xxxx
                 (true at standard parallel lat) or radius/lat (radius  in  UNIT  from  origin  to  the  oblique
                 latitude  lat). Note if 1:xxxx is used then to specify horizon you must also specify the lat as
                 +-90 to avoid ambiguity.

          MISCELLANEOUS PROJECTIONS:

          -Jh[lon0/]scale or -JH[lon0/]width (Hammer [E]).
                 Give the central meridian lon0 (optional) and scale along equator (1:xxxx or UNIT/degree).

          -Ji[lon0/]scale or -JI[lon0/]width (Sinusoidal [E]).
                 Give the central meridian lon0 (optional) and scale along equator (1:xxxx or UNIT/degree).

          -Jkf[lon0/]scale or -JKf[lon0/]width (Eckert IV) [E]).
                 Give the central meridian lon0 (optional) and scale along equator (1:xxxx or UNIT/degree).

          -Jk[s][lon0/]scale or -JK[s][lon0/]width (Eckert VI) [E]).
                 Give the central meridian lon0 (optional) and scale along equator (1:xxxx or UNIT/degree).

          -Jn[lon0/]scale or -JN[lon0/]width (Robinson).
                 Give the central meridian lon0 (optional) and scale along equator (1:xxxx or UNIT/degree).

          -Jr[lon0/]scale -JR[lon0/]width (Winkel Tripel).
                 Give the central meridian lon0 (optional) and scale along equator (1:xxxx or UNIT/degree).

          -Jv[lon0/]scale or -JV[lon0/]width (Van der Grinten).
                 Give the central meridian lon0 (optional) and scale along equator (1:xxxx or UNIT/degree).

          -Jw[lon0/]scale or -JW[lon0/]width (Mollweide [E]).
                 Give the central meridian lon0 (optional) and scale along equator (1:xxxx or UNIT/degree).

          NON-GEOGRAPHICAL PROJECTIONS:
          -Jp[a]scale[/origin][r|z] or -JP[a]width[/origin][r|z] (Polar coordinates (theta,r))

          Optionally insert a after -Jp [ or -JP] for azimuths CW from North instead of directions CCW from East
          [Default]. Optionally append /origin in degrees to indicate an angular offset [0]).  Finally, append r
          if r is elevations in degrees (requires s >= 0 and n <= 90) or z if you want to annotate depth  rather
          than radius [Default]. Give scale in UNIT/r-unit.
          -Jxx-scale[/y-scale] or -JXwidth[/height] (Linear, log, and power scaling)

          Give  x-scale  (1:xxxx or UNIT/x-unit) and/or y-scale (1:xxxx or UNIT/y-unit); or specify width and/or
          height in UNIT. y-scale=x-scale if not specified separately and using 1:xxxx implies that  x-unit  and
          y-unit  are  in meters.  Use negative scale(s) to reverse the direction of an axis (e.g., to have y be
          positive down). Set height or width to 0 to have it recomputed based on the implied scale of the other
          axis. Optionally, append to x-scale, y-scale, width or height one of the following:

              d      Data are geographical coordinates (in degrees).

              l      Take log10 of values before scaling.

              ppower Raise values to power before scaling.

              t      Input coordinates are time relative to TIME_EPOCH.

              T      Input coordinates are absolute time.

              For mixed axes with only one geographic axis you may need to set -f as well.

       When  -J  is  used  without any further arguments, or just with the projection type, the arguments of the
       last used -J, or the last used -J with that projection type, will be used.

       -Jz|Zparameters
              Set z-axis scaling; same syntax as -Jx.

       -J<proj4>|EPSG:n
              Starting at GMT6 it is possible to use the PROJ.4 library to do coordinate and  datum  transforms.
              This is achieved via GDAL so it requires that GMT build is linked to that library. It is, however,
              beyond the scope of this manual to document the PROJ.4 syntax (that is the syntax of the proj  and
              cs2cs programs) so users are referred to it http://proj4.org/apps/index.html for the details.

              The  usage  of PROJ.4 follows very closely the syntax of proj and cs2cs. The projection parameters
              are encapsulated under the -J option. Because there are normally  several  parameters  defining  a
              referencing  system  separated by spaces (in PROJ.4 or GDAL) we can either use double quotes as in
              -J+proj=merc   +ellps=WGS84    +units=m”    or    just    glue    all    parameters    like    in
              -J+proj=merc+ellps=WGS84+units=m.

              Using  EPSG  codes is also possible (but need the setting of the GDAL_DATA environment variable to
              point to the GDAL’s data sub-directory). For example -JEPSG:4326 sets the WGS-84 system.

              For mapproject and grdproject we can go directly from the referencing system A to  B  without  the
              intermediate  step  of  converting to geographic coordinates.  That is obtained (like in cs2cs) by
              using the +to keyword. Example: -JEPSG:4326+to+proj=aeqd+ellps=WGS84+units=m. A much awaited bonus
              is also that we now do not need to set -R to do point coordinate conversions.

              While  for  point  and  grid  conversions  done by mapproject and grdproject we can use all PROJ.4
              projections, the situations is, however, rather more limited for mapping purposes.  Here, only the
              subset  of  the PROJ.4 projections that can be mapped into the GMT projections syntax is available
              to use. Another aspect that is not present in PROJ.4, because it’s not a mapping library,  is  how
              to  set  the  map  scale  or  map  dimension.  We  introduced  the  two extensions +width=size and
              +scale=1:xxxx that work exactly like the map width and scale in classical GMT. It is also  allowed
              to  provide  the  scale  (but  NOT  the  width) by appending the string “/1:xxx” to the end of the
              projection parameters.

       -Rxmin/xmax/ymin/ymax[+r][+uunit]
              xmin, xmax, ymin, and ymax specify the region of interest.  For geographic regions,  these  limits
              correspond  to  west,  east,  south,  and  north and you may specify them in decimal degrees or in
              [±]dd:mm[:ss.xxx][W|E|S|N] format. Append +r if lower left and upper  right  map  coordinates  are
              given  instead  of  west/east/south/north.  The two shorthands -Rg and -Rd stand for global domain
              (0/360 and -180/+180 in longitude respectively, with -90/+90 in latitude).  Set geographic regions
              by    specifying   ISO   country   codes   from   the   Digital   Chart   of   the   World   using
              -Rcode1,code2,…[+r|R[incs]] instead: Append  one  or  more  comma-separated  countries  using  the
              2-character  ISO 3166-1 alpha-2 convention.  To select a state of a country (if available), append
              .state, e.g, US.TX for Texas.  To specify a whole continent, prepend = to  any  of  the  continent
              codes  AF  (Africa), AN (Antarctica), AS (Asia), EU (Europe), OC (Oceania), NA (North America), or
              SA (South America).  Use +r to modify the bounding box coordinates  from  the  polygon(s):  Append
              inc,  xinc/yinc,  or  winc/einc/sinc/ninc to adjust the region to be a multiple of these steps [no
              adjustment]. Alternatively, use +R to extend the region outward by adding these increments instead
              [no  extension].   Alternatively  for  grid  creation,  give  -Rcodex0/y0/nx/ny,  where  code is a
              2-character combination of L, C, R (for left, center, or right) and T, M, B for  top,  middle,  or
              bottom.  e.g.,  BL  for  lower left.  This indicates which point on a rectangular region the x0/y0
              coordinate refers to, and the grid dimensions nx and ny with grid  spacings  via  -I  is  used  to
              create the corresponding region.  Alternatively, specify the name of an existing grid file and the
              -R settings (and grid spacing, if applicable) are copied from the grid. When -R  is  used  without
              any  further arguments, the values from the last use of -R in a previous GMT command will be used.
              For calendar time coordinates you may either give (a) relative  time  (relative  to  the  selected
              TIME_EPOCH  and  in  the  selected TIME_UNIT; append t to -JX|x), or (b) absolute time of the form
              [date]T[clock] (append T to -JX|x). At least one of date and clock  must  be  present;  the  T  is
              always  required.  The  date  string must be of the form [-]yyyy[-mm[-dd]] (Gregorian calendar) or
              yyyy[-Www[-d]] (ISO week calendar), while the clock string must be of the form hh:mm:ss[.xxx]. The
              use  of  delimiters  and  their  type  and positions must be exactly as indicated (however, input,
              output and plot formats are customizable; see gmt.conf).  You can  also  use  Cartesian  projected
              coordinates  compatible  with  the chosen projection.  Append the length unit via the +u modifier,
              (e.g., -R-200/200/-300/300+uk for a 400 by 600 km rectangular  area  centered  on  the  projection
              center  (0,  0).  These  coordinates  are  internally  converted  to  the corresponding geographic
              (longitude, latitude) coordinates for the lower  left  and  upper  right  corners.  This  form  is
              convenient  when  you want to specify a region directly in the projected units (e.g., UTM meters).
              For Cartesian data in radians you can also use [±][s]pi[f], for  optional  integer  scales  s  and
              fractions f.

       In  case  of perspective view -p, a z-range (zmin, zmax) can be appended to indicate the third dimension.
       This needs to be done only when using the -Jz option, not when using only the -p option.  In  the  latter
       case a perspective view of the plane is plotted, with no third dimension.

       -U[label][+c][+jjust][+odx/dy]
              Draw the GMT Unix System time stamp on the plot.  By appending +jjust and/or +odx/dy, 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, +jBL+o0/0 will align the lower left corner of the
              time stamp with the bottom left corner of the plot [BL]. Optionally, append a label,  or  give  +c
              which  will  plot  the  command  string.  The GMT parameters MAP_LOGO, MAP_LOGO_POS, FONT_LOGO and
              FORMAT_TIME_STAMP can affect the appearance; see the gmt.conf man  page  for  details.   The  time
              string will be in the locale set by the environment variable TZ (generally local time).

       -V[level]
              Select  verbose  mode,  which  will  send  progress  reports  to stderr.  Choose among 6 levels of
              verbosity; each level adds more messages: q - Complete silence, not even fatal error messages  are
              produced.   n  -  Normal  verbosity:  produce  only  fatal  error  messages.   c  -  Produce  also
              compatibility warnings (same as when -V is omitted).  v  -  Produce  also  warnings  and  progress
              messages  (same  as  -V  only).   l  -  Produce also detailed progress messages.  d - Produce also
              debugging messages.

       -X[a|c|f|r][xshift[u]]

       -Y[a|c|f|r][yshift[u]]
              Shift plot origin relative to the current origin by  (xshift,yshift)  and  optionally  append  the
              length  unit  (c,  i,  or  p). You can prepend a to shift the origin back to the original position
              after plotting, prepend c to center the plot on the center of the paper  (optionally  add  shift),
              prepend  f  to  shift the origin relative to the fixed lower left corner of the page, or prepend r
              [Default] to move  the  origin  relative  to  its  current  location.  For  overlays  the  default
              (xshift,yshift)  is  (r0),  otherwise  it  is  (r1i).  When  -X or -Y are used without any further
              arguments, the values from the last use of that option in a previous GMT  command  will  be  used.
              Note  that  -X  and  -Y can also access the previous plot dimensions w and h and construct offsets
              that involves them.  For instance, to move the origin up 2 cm beyond the height  of  the  previous
              plot, use -Yh+2c.  To move the origin half the width to the right, use -Xw/2.

       -a[col=]name[]
              Control  how  aspatial data are handled in GMT during input and output.  Reading OGR/GMT-formatted
              files: To assign certain aspatial data items to GMT data columns, give one or more comma-separated
              associations col=name, where name is the name of an aspatial attribute field in a OGR/GMT file and
              whose value we wish to use as data input for column col. In addition, to assign an aspatial  value
              to  non-column  data,  you may specify col as D for distance, G for fill, I for ID, L for label, T
              for text, W for pen, and Z for value [e.g., used to look up color via a CPT].   If  you  skip  the
              leading  “col=”  in  the  argument  then  we  supply  (and automatically increment) a column value
              starting at 2.  Give just -a to select all aspatial  items  to  be  added  to  the  input  record.
              Writing   OGR/GMT-formatted   files:   To   write   OGR/GMT-formatted  files,  give  one  or  more
              comma-separated associations col=name[:type], with an  optional  data  type  from  DOUBLE,  FLOAT,
              INTEGER, CHAR, STRING, DATETIME, or LOGICAL [DOUBLE]. To extract information from GMT multisegment
              headers encoded in the -Ddistance, -Gfill, -IID, -Llabel,  -Ttext,  -Wpen,  or  -Zvalue  settings,
              specify  COL  as D, G, I, L, T, W or Z, respectively; type will be set automatically. Finally, you
              must append +ggeometry, where geometry is either POINT, LINE, or POLY. Optionally, prepend  M  for
              multi-versions  of  these geometries. To force the clipping of features crossing the Dateline, use
              upper-case +G instead. See GMT Appendix Q for details of the OGR/GMT file format.

       -bi[ncols][type][w][+l|b]
              Select native binary format for primary input (secondary inputs are always ASCII).  Here, ncols is
              the  number  of data columns of given type, which must be one of c (int8_t, aka char), u (uint8_t,
              aka unsigned char), h (int16_t, 2-byte signed int), H (uint16_t, 2-byte unsigned int), i (int32_t,
              4-byte  signed  int),  I  ((capital i) uint32_t, 4-byte unsigned int), l ((lower case el) int64_t,
              8-byte signed int), L (uint64_t, 8-byte unsigned int), f (4-byte single-precision  float),  and  d
              (8-byte  double-precision  float).  In addition, use x to skip ncols bytes anywhere in the record.
              For records with mixed types, simply append additional comma-separated combinations of ncols  type
              (no  space).  Append  w to any item to force byte-swapping. Alternatively, append +l|b to indicate
              that the entire data file should be read as little- or big-endian,  respectively.  The  cumulative
              number  of  ncols may exceed the columns actually needed by the program. If ncols is not specified
              we assume that type applies to all columns and that ncols is implied by  the  expectation  of  the
              program.  If the input file is netCDF, no -b is needed; simply append ?var1/var2/ to the filename
              to specify the variables to be read.

       -bo[ncols][type][w][+l|b]
              Select native binary output. Here, ncols is the actual number of data columns of type type,  which
              must  be  one  of  c, u, h, H, i, I (capital i), l (lower case ell), L, f, and d (see -bi).  For a
              mixed-type output record, append additional comma-separated combinations of ncols type (no space).
              Append  w  to  any  item to force byte-swapping or +l|b for byte-swapping of the entire record. If
              ncols is not specified we assume that type applies to all columns and that ncols is implied by the
              default output of the program. Note: NetCDF file output is not supported.

       -c[row,col |index]
              Used  to  advance to the selected subplot panel.  Only allowed when in subplot mode.  Available to
              all plot modules.  If no arguments are given then we advance to the next  panel  in  the  selected
              order.  If  no  -c  is  given and we just entered subplot mode then the first panel (top, left) is
              selected.  Instead of row, col you may give the one-dimensional index which depends on  the  order
              you set via -A when the subplot was defined. Note: row, col, and index all start at 0.

       -d[i|o]nodata
              Control  how  user-coded  missing  data  values are translated to official NaN values in GMT.  For
              input data we replace any value that equals nodata with NaN. For output data we  replace  any  NaN
              with the chosen nodata value.  Use -di or -do to only affect input or output.

       -dinodata
              Examine  all input columns and if any item equals nodata we interpret this value as a missing data
              item and substitute the value NaN.

       -donodata
              Examine all output columns and if any item equals NAN we substitute it  with  the  chosen  missing
              data value nodata.

       -e[~]”pattern” | -e[~]/regexp/[i]
              Only  accept ASCII data records that contains the specified pattern.  To reverse the search, i.e.,
              to only accept data record that do not contain the specified pattern, use -e~. Should your pattern
              happen  to  start  with  ~ you need to escape this character with a backslash [Default accepts all
              data records]. For  matching  data  records  against  extended  regular  expressions  enclose  the
              expression in slashes.  Append i for case-insensitive matching.  For a list of such patterns, give
              +ffile with one pattern per line.  To give a single pattern starting with +f,  escape  it  with  a
              backslash.

       -f[i|o]colinfo
              Specify  the data types of input and/or output columns (time or geographical data). Specify i or o
              to make this apply only to input or output [Default applies to both]. Give one or more columns (or
              column  ranges)  separated by commas, or use -f multiple times (column ranges must be given in the
              format start[:inc]:stop, where inc defaults to 1 if not specified).  Append T  (absolute  calendar
              time),  t  (relative  time  in  chosen  TIME_UNIT  since TIME_EPOCH), x (longitude), y (latitude),
              p[unit] (projected x,y map coordinates in given unit [meter]) or f (floating point) to each column
              or column range item. Shorthands -f[i|o]g means -f[i|o]0x,1y (geographic coordinates) and -f[i|o]c
              means -f[i|o]0-1f (Cartesian coordinates)

       -g[a]x|y|d|X|Y|D|[col]zgap[u][+n|p]
              Examine the spacing between consecutive data points in order to impose breaks in the line.  Append
              x|X  or  y|Y  to  define  a  gap  when  there  is a large enough change in the x or y coordinates,
              respectively, or d|D  for  distance  gaps;  use  upper  case  to  calculate  gaps  from  projected
              coordinates.  For gap-testing on other columns use [col]z; if col is not prepended the it defaults
              to 2 (i.e., 3rd column).  Append gap and optionally a unit u and modifiers +n  or  +p.   Here,  +n
              means  previous  minus current column value must exceed gap to be a gap and +p means current minus
              previous column value must exceed gap. Otherwise the absolute value of the difference must  exceed
              gap.  For  geographic  data  (x|y|d),  the  unit  u may be arc degree, minute, or second, or meter
              [Default], foot, kilometer, Mile, nautical mile, or  survey  foot.  For  projected  data  (X|Y|D),
              choose  from  inch,  centimeter,  or point [Default unit set by PROJ_LENGTH_UNIT]. Note: For x|y|z
              with time data the unit is instead controlled by TIME_UNIT. Repeat the option to specify  multiple
              criteria,  of  which  any  can be met to produce a line break. Issue an additional -ga to indicate
              that all criteria must be met instead.

       -h[i|o][n][+c][+d][+rremark][+ttitle]
              Primary input file(s) has header record(s). If used, the  default  number  of  header  records  is
              IO_N_HEADER_RECS  [1].  Use -hi if only the primary input data should have header records [Default
              will write out header records if the input data have them]. Blank lines and lines starting with  #
              are  always  skipped.  For  output you may request additional headers to be written via the option
              modifiers, and use +d to remove existing header records. Append +c to issue a header comment  with
              column  names  to  the  output  [none].   Append  +r to add a remark comment to the output [none].
              Append +t to add a title comment to the output [none].  These optional strings may  contain  n  to
              indicate  line-breaks).  If used with native binary data we interpret n to instead mean the number
              of bytes to skip on input or pad on output.

       -icols[+l][+sscale][+ooffset][,][,t[word]]
              Select specific data columns for primary input, in arbitrary order. Columns  not  listed  will  be
              skipped.  Give  individual  columns  (or  column  ranges in the format start[:inc]:stop, where inc
              defaults to 1 if not specified) separated by commas [Default reads all columns in order,  starting
              with  the  first column (0)]. Columns may be repeated.  To each column, optionally add any of  the
              following: +l takes log10 of the input values first; +sscale, subsequently multiplies by  a  given
              scale  factor [1]; +ooffset, finally adds a given offset [0].  Normally, any trailing text is read
              but when i is used you must explicitly add the column t to retain  the  text.  To  only  ingest  a
              single  word  from the trailing text, append the word number (first word is 0).  Finally, -in will
              simply read the numerical input and skip any trailing text.

       -je|f|g
              Determine how spherical distances are calculated in modules that support this.  By  default  (-jg)
              we  perform great circle distance calculations and parameters such as distance increments or radii
              will be compared against calculated great circle distances. To simplify and speed up  calculations
              you  can  select Flat Earth mode (-jf) which gives an approximate and fast result.  Alternatively,
              you can select ellipsoidal  (-je)  or  geodesic  mode  for  the  highest  precision  (and  slowest
              calculation  time).   All  spherical  distance  calculations  depends  on  the  current  ellipsoid
              (PROJ_ELLIPSOID), the definition of the mean radius (PROJ_MEAN_RADIUS), and the  specification  of
              latitude  type  (PROJ_AUX_LATITUDE).   Geodesic distance calculations is also controlled by method
              (PROJ_GEODESIC).

       -l[label][+dpen][+ffont][+ggap][+hheader][+jjust][+l[code/]txt][+ncols][+ssize][+v[pen]][+wwidth][+xscale]
              [beta version] Add a map legend entry to the session legend information file for the current plot.
              Optionally append a text label to describe the entry.  Several modifiers allow further changes  to
              the legend (to be built when legend is called): Use +d to draw a horizontal line before the legend
              entry is placed [no line], use +f to set the font used for the legend header [FONT_TITLE], use  +g
              to  add some vertical space [0], use +h to add a legend header [no header], +j to set placement of
              the legend [TR], use +l to set a line text; prepend a horizontal justification code  L,  C,  or  R
              [C],  use +n to change the number of columns used to set the following legend items [1], use +s to
              override the size of the current symbol for the legend or set a  length  if  plotting  a  line  or
              contour  [same  as plotted], use +v to start and +vpen to stop drawing vertical line from previous
              to current horizontal line [no vertical line], use +w to set legend width [auto], and use  +xscale
              to  resize  all  symbol  and length sizes in the legend.  Default pen is given by MAP_DEFAULT_PEN.
              Note that +h, +j, +w, and +x will only take effect if given on the very  first  -l  option  for  a
              plot.   The  +n modifier, if used on the first -l option, affects the legend width (unless set via
              +w); otherwise it just subdivides the available width among the specified columns.  The  automatic
              legend  has a fixed white background with a solid black pen outline and offset 0.2 cm from the map
              frame.  The modifiers largely reflect legend codes described in legend, which provide more details
              and  customization.   If legend is not called explicitly we will call it implicitly when finishing
              the plot via end.

       -n[b|c|l|n][+a][+bBC][+c][+tthreshold]
              Select grid interpolation mode by adding b for B-spline smoothing, c for bicubic interpolation,  l
              for  bilinear  interpolation,  or  n  for  nearest-neighbor value (for example to plot categorical
              data). Optionally, append +a to switch off antialiasing (where supported). Append +bBC to override
              the  boundary  conditions used, adding g for geographic, p for periodic, or n for natural boundary
              conditions. For the latter two you may append x or y to specify just one direction, otherwise both
              are  assumed.  Append  +c  to  clip  the  interpolated grid to input z-min/max [Default may exceed
              limits]. Append +tthreshold to control how close to nodes with NaNs the interpolation will  go.  A
              threshold  of  1.0  requires all (4 or 16) nodes involved in interpolation to be non-NaN. 0.5 will
              interpolate about half way from a non-NaN value; 0.1 will go about 90% of the way, etc.   [Default
              is  bicubic  interpolation  with antialiasing and a threshold of 0.5, using geographic (if grid is
              known to be geographic) or natural boundary conditions].

       -ocols[,…][t[word]]
              Select specific data columns for primary output, in arbitrary order. Columns not  listed  will  be
              skipped. Give columns (or column ranges in the format start[:inc]:stop, where inc defaults to 1 if
              not specified) separated by commas.  Columns may be repeated.   [Default  writes  all  columns  in
              order].   Normally,  any trailing text in the internal records will be written but when -o is used
              you must explicitly add the column t. To only output a single word from the trailing text,  append
              the  word  number (first word is 0).  Finally, -on will simply write the numerical output only and
              skip any trailing text.  Note: If -i is also used then columns given to -o correspond to the order
              after the -i selection and not the columns in the original record.

       -p[x|y|z]azim[/elev[/zlevel]][+wlon0/lat0[/z0]][+vx0/y0]
              Selects  perspective view and sets the azimuth and elevation of the viewpoint [180/90]. When -p is
              used in consort with -Jz or -JZ, a third value can be appended which indicates  at  which  z-level
              all  2D  material,  like the plot frame, is plotted (in perspective). [Default is at the bottom of
              the z-axis]. Use -px or -py to plot against the “wall” x = level or y = level (default is  on  the
              horizontal  plane, which is the same as using -pz). For frames used for animation, note we fix the
              center of your data domain.  Specify another center using a particular world coordinate point with
              +wlon0/lat0[/z0])  which  will project to the center of your page size, or specify the coordinates
              of the projected 2-D view point with +vx0/y0. When -p is used without any further  arguments,  the
              values  from  the  last  use of -p in a previous GMT command will be used.  Alternatively, you can
              perform a simple rotation about the z-axis by just giving the rotation angle.  Optionally, use  +v
              or +w to select another axis location than the plot origin.

       -r[g|p]
              Force  gridline  or  pixel node registration [Just -r sets pixel registration].  If no -r is given
              then gridline registration is selected.  (Node registrations are defined in Section option_nodereg
              of the GMT Technical Reference and Cookbook.)

       -s[cols][+a|+r]
              Suppress  output  for records whose z-value equals NaN [Default outputs all records]. Append +a to
              skip records where at least one field equal NaN, or append +r to reverse  the  suppression,  i.e.,
              only  output  the records whose z-value equals NaN. Alternatively, indicate a comma-separated list
              of all columns or column ranges to consider for this NaN test (Column ranges must be given in  the
              format start[:inc]:stop, where inc defaults to 1 if not specified).

       -t[transp]
              Set  transparency  level  for  an overlay, in (0-100] percent range. [Default is 0, i.e., opaque].
              Only visible when PDF or raster format output is selected.

       -x[[-]n]
              Limit the number of cores to be used in any OpenMP-enabled multi-threaded algorithms.  By  default
              we  try  to  use  all  available  cores.   Append  n  to only use n cores (if too large it will be
              truncated to the maximum cores available).  Finally, give a negative n to select (all -  n)  cores
              (or  at  least  1  if  n  equals  or exceeds all).  The -x option is only available to GMT modules
              compiled with OpenMP support.

       -:[i|o]
              Swap 1st and 2nd column on input and/or output [Default is no swapping]. Append i to select  input
              only  or  o to select output only. [Default affects both]. This option is typically used to handle
              (latitude, longitude) files; see also -icols[l][sscale][ooffset][,].

       -^ or just -
              Print a short message about the syntax of the command, then exits (NOTE: on Windows just use -).

       -+ or just +
              Print an extensive usage (help) message, including the explanation of any  module-specific  option
              (but not the GMT common options), then exits.

       -? or no arguments
              Print a complete usage (help) message, including the explanation of all options, then exits.

       --PAR=value
              Temporarily override a GMT default setting; repeatable. See /gmt.conf for parameters.

   Specifying Color
       color  The color of lines, areas and patterns can be specified by a valid color name, by a gray shade (in
              the range 0-255), by a decimal color code (r/g/b, each in range 0-255; h-s-v, ranges  0-360,  0-1,
              0-1;  or  c/m/y/k,  each in range 0-1), or by a hexadecimal color code (#rrggbb, as used in HTML).
              For transparency, append @transparency in the 0-100 percent range [0 or opaque] (Only visible when
              PDF  or raster format output is selected.).  See gmtcolors for more information and a full list of
              color names.

   Specifying Fill
       fill   The attribute fill specifies the solid shade or solid color (see Specifying Color  above)  or  the
              pattern  used  for  filling  polygons.   Patterns are specified as ppattern, where pattern set the
              number of the built-in pattern (1-90) or the name of a raster image file. The optional +rdpi  sets
              the  resolution  of  the  image [1200]. For 1-bit rasters: use upper case P  for inverse video, or
              append +fcolor and/or +bcolor  to  specify  fore-  and  background  colors  (use  color  =  -  for
              transparency).  See  GMT  Cookbook  & Technical Reference Appendix E for information on individual
              built-in patterns.

   Specifying Fonts
       font   The attributes of text fonts as defined by font is a comma delimited list of  size,  fonttype  and
              fill, each of which is optional. size is the font size (usually in points) but c or i can be added
              to indicate other units. fonttype is the name (case sensitive!) of  the  font  or  its  equivalent
              numerical  ID  (e.g., Helvetica-Bold or 1). fill specifies the gray shade, color or pattern of the
              text (see Specifying Fill above). Optionally, you may append =pen to the fill value  in  order  to
              draw  a  text  outline.  If you want to avoid that the outline partially obscures the text, append
              append =~pen instead; in that case only half the linewidth is plotted on the outside of  the  font
              only.   If  an  outline is requested, you may optionally skip the text fill by setting it to -, in
              which case the full pen width is always used. If any of  the  font  attributes  is  omitted  their
              default or previous setting will be retained.

              The 35 available fonts (plus 4 optional Japanese fonts) are:

              0.   Helvetica

              1.   Helvetica-Bold

              2.   Helvetica-Oblique

              3.   Helvetica-BoldOblique

              4.   Times-Roman

              5.   Times-Bold

              6.   Times-Italic

              7.   Times-BoldItalic

              8.   Courier

              9.   Courier-Bold

              10.  Courier-Oblique

              11.  Courier-BoldOblique

              12.  Symbol

              13.  AvantGarde-Book

              14.  AvantGarde-BookOblique

              15.  AvantGarde-Demi

              16.  AvantGarde-DemiOblique

              17.  Bookman-Demi

              18.  Bookman-DemiItalic

              19.  Bookman-Light

              20.  Bookman-LightItalic

              21.  Helvetica-Narrow

              22.  Helvetica-Narrow-Bold

              23.  Helvetica-Narrow-Oblique

              24.  Helvetica-Narrow-BoldOblique

              25.  NewCenturySchlbk-Roman

              26.  NewCenturySchlbk-Italic

              27.  NewCenturySchlbk-Bold

              28.  NewCenturySchlbk-BoldItalic

              29.  Palatino-Roman

              30.  Palatino-Italic

              31.  Palatino-Bold

              32.  Palatino-BoldItalic

              33.  ZapfChancery-MediumItalic

              34.  ZapfDingbats

              35.  Ryumin-Light-EUC-H

              36.  Ryumin-Light-EUC-V

              37.  GothicBBB-Medium-EUC-H

              38.  GothicBBB-Medium-EUC-V

   Specifying Pens
       pen    The  attributes of lines and symbol outlines as defined by pen is a comma-delimited list of width,
              color and style, each of which is optional. width can be indicated as a measure (in  points  (this
              is  the  default),  centimeters,  or  inches) or as faint, default, thin[ner|nest], thick[er|est],
              fat[ter|test], or obese. color specifies a gray shade or color (see Specifying Color above). style
              can  be  any  of  ‘solid’,  ‘dashed’ ‘dotted’, ‘dashdot’, or ‘dotdash’, or a custom combination of
              dashes ‘-‘ and dots ‘.’. If any of the attributes is omitted their  default  or  previous  setting
              will  be  retained.  See  GMT  Cookbook  &  Technical Reference Specifying pen attributes for more
              information.

ASCII FORMAT PRECISION

       The ASCII output formats of numerical data are controlled by parameters in your gmt.conf file.  Longitude
       and  latitude  are  formatted  according  to  FORMAT_GEO_OUT,  absolute  time  is  under  the  control of
       FORMAT_DATE_OUT and FORMAT_CLOCK_OUT, whereas general floating point values are  formatted  according  to
       FORMAT_FLOAT_OUT. Be aware that the format in effect can lead to loss of precision in ASCII output, which
       can lead to various problems downstream. If you find the output is not  written  with  enough  precision,
       consider   switching   to   binary  output  (-bo  if  available)  or  specify  more  decimals  using  the
       FORMAT_FLOAT_OUT setting.

GRID FILE FORMATS

       By default GMT writes out grids as single precision floats in  a  COARDS-complaint  netCDF  file  format.
       However,  GMT  is  able  to produce and read grid files in many other commonly used grid file formats and
       also facilitates so called “packing” of grids, writing out floating point data as 1- or 2-byte  integers.
       To    specify    the    precision,    scale    and    offset,    the   user   should   add   the   suffix
       [=id][+sscale][+ooffset][+ninvalid], where id is a two-letter identifier of the grid type and  precision,
       and  the  scale,  offset  and  invalid  are the arguments of optional modifiers to be applied to all grid
       values,  Here, invalid is the value used to indicate missing data. In case the id is not provided, as  in
       +sscale  than  a  id=nf is assumed.  When reading grids, the format is generally automatically recognized
       from almost all of those formats that GMT and GDAL combined offer. If not, the same suffix can  be  added
       to input grid file names.  See grdconvert and Section grid-file-format of the GMT Technical Reference and
       Cookbook for more information.

       When reading a netCDF  file  that  contains  multiple  grids,  GMT  will  read,  by  default,  the  first
       2-dimensional  grid  that  can  find  in  that  file.  To coax GMT into reading another multi-dimensional
       variable in the grid file, append ?varname to the file name, where varname is the name of  the  variable.
       Note that you may need to escape the special meaning of ? in your shell program by putting a backslash in
       front of it, or by placing the filename and suffix between quotes or double quotes. The  ?varname  suffix
       can  also  be  used  for  output  grids  to  specify a variable name different from the default: “z”. See
       grdconvert and Sections modifiers-for-CF and grid-file-format of the GMT Technical Reference and Cookbook
       for more information, particularly on how to read splices of 3-, 4-, or 5-dimensional grids.

CLASSIC MODE OPTIONS

       These options are only used in classic mode and are listed here just for reference.

       -K     More PostScript code will be appended later [Default terminates the plot system]. Required for all
              but the last plot command when building multi-layer plots.

       -O     Selects Overlay plot mode [Default initializes a new plot system].  Required for all but the first
              plot command when building multi-layer plots.

       -P     Select  “Portrait”  plot orientation [Default is “Landscape”; see gmt.conf or gmtset to change the
              PS_PAGE_ORIENTATION parameter, or supply --PS_PAGE_ORIENTATION=orientation on the command line].

SEE ALSO

       Look up the individual man pages for more details and full  syntax.  Run  gmt  --help  to  list  all  GMT
       programs and to show all installation directories. For an explanation of the various GMT settings in this
       man page (like FORMAT_FLOAT_OUT), see the man page of the GMT configuration file gmt.conf. Information is
       also available on the GMT documentation site https://docs.generic-mapping-tools.org/

COPYRIGHT

       2019, The GMT Team.