psscale

       psscale - Create grayscale or colorscale for maps

SYNOPSIS

       psscale   -Dxpos/ypos/length/width[h]  [  -Btickinfo  ]  [
       -Ccpt_file ] [ -E[length] ] [ -I[max_intens] ] [ -K ] [ -L
       ]  [ -M ] [ -Ndpi ] [ -O ] [ -P ] [ -U[/dx/dy/][label] ] [
       -V  ] [ -Xx-shift ] [ -Yy-shift ] [ -Zzfile ] [ -ccopies ]

DESCRIPTION

       psscale plots grayscales or colorscales on maps. Both hor­
       izontal and vertical scales are supported.  For  cpt_files
       with  gradational colors (i.e., the lower and upper bound­
       ary of an interval have different  r/g/b  values)  psscale
       will interpolate to give a continuous scale. Variations in
       intensity due to shading/illumination may be displayed  by
       setting the option -I. Colors may be spaced according to a
       linear scale, all be equal size, or by  providing  a  file
       with individual tile widths.

       -D     Defines  the  position of the center/top (for hori­
              zontal scale) or center/left (for  vertical  scale)
              and  the dimensions of the scale. Append h to get a
              horizontal scale [Default is vertical].

OPTIONS

       No space between the option flag and the associated  argu­
       ments.

       -B     Set  anotation, tick, and gridline interval for the
              colorbar. The xaxis label will plot beneath a hori­
              zontal  bar (or vertically to the right of a verti­
              cal bar). As an option, use the yaxis label to plot
              the data unit to the right of a horizontal bar (and
              above a vertical bar).  If no values are  provided,
              the  default is to anotate every color level (which
              may be overridden by ULB flags in  the  cpt  file).
              Note  that since vertical labels will be plotted as
              a column of individual characters, no octal  escape
              characters imbedded in the label are allowed.

       -C     cpt_file  is the color palette file to be used.  By
              default all color changes are anotated.  To  use  a
              subset,  add an extra column to the cpt-file with a
              L, U, or B to anotate Lower, Upper, or  Both  color
              segment  boundaries  (but  see  -B).  If not given,
              psscale will read stdin. As  for  grdview,  psscale
              can  understand  pattern  specifications in the cpt
              file.

       -E     Add sidebar triangles for back- and foreground col­
              ors. Optionally, append triangle height [Default is
              half the barwidth].
              of intensities from + to - max_intens. If not spec­
              ified, 1.0 is used. [Default is no illumination]

       -K     More  PostScript  code  will  be   appended   later
              [Default terminates the plot system].

       -L     Gives  equal-sized color rectangles. Default scales
              rectangles according to the z-range in the cpt-file
              (Also see -Z).

       -M     Force  a  monochrome graybar using the (television)
              YIQ transformation.

       -N     Effective dots-per-inch for the  rectangular  image
              making up the color scale [300].

       -O     Selects  Overlay  plot  mode [Default initializes a
              new plot system].

       -P     Selects Portrait  plotting  mode  [GMT  Default  is
              Landscape, see gmtdefaults to change this].

       -U     Draw Unix System time stamp on plot. User may spec­
              ify where the lower left corner of the stamp should
              fall  on  the page relative to lower left corner of
              plot. Optionally, append a label, or c (which  will
              plot  the  command  string.).  The  GMT  parameters
              UNIX_TIME and UNIX_TIME_POS can affect the  appear­
              ance; see the gmtdefaults man page for details.

       -V     Selects  verbose  mode,  which  will  send progress
              reports to stderr [Default runs "silently"].

       -X -Y  Shift origin of plot by (x-shift,y-shift).  Prepend
              a  for  absolute  coordinates; the default (r) will
              reset plot origin.

       -Z     File  with  colorbar-width  per  color  entry.   By
              default,  width  of entry is scaled to color range,
              i.e., z = 0-100  gives  twice  the  width  as  z  =
              100-150 (Also see -L).

       -c     Specifies the number of plot copies. [Default is 1]

EXAMPLES

       To append a vertical colorscale  (7.5  cm  long;  1.25  cm
       wide)  to  the  right  of a plot that is 6 inch wide and 4
       inch high, using illumination, and show  back-  and  fore­
       ground colors, and anotating every 5 units, try

       psscale   -D6.5i/2i/7.5c/1.25c   -O   -Ccolors.cpt  -I  -E
       -B5:BATHYMETRY:/:m: >> map.ps
       When the cpt file is discrete and no illumination is spec­
       ified,  the  color bar will be painted using polygons. For
       all other cases we must paint with an  image.  Some  color
       printers  may  give  slightly different colors for the two
       methods given identical RGB values.

SEE ALSO

       gmt(l), makecpt(l), grd2cpt(l)