NAME¶
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 horizontal and
vertical scales are supported. For cpt_files with gradational colors (i.e.,
the lower and upper boundary 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 horizontal 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 arguments.
- -B
- Set anotation, tick, and gridline interval for the colorbar. The xaxis
label will plot beneath a horizontal bar (or vertically to the right of a
vertical 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 colors. Optionally, append
triangle height [Default is half the barwidth].
- -I
- Add illumination effects. Optionally, set the range of intensities from +
to - max_intens. If not specified, 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). If set, any equal
interval annotation set with -B will be ignored.
- -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].
- -bo
- Selects binary output. Append s for single precision [Default is
double].
- -P
- Selects Portrait plotting mode [GMT Default is Landscape, see
gmtdefaults to change this].
- -U
- Draw Unix System time stamp on plot. User may specify 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 appearance; 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 foreground colors, and anotating every 5 units, try
psscale
-D6.5
i/2
i/7.5
c/1.25
c -O
-Ccolors.cpt
-I -E -B5:BATHYMETRY:/:m: >> map.ps
NOTES¶
When the cpt file is discrete and no illumination is specified, 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(1gmt),
makecpt(1gmt),
grd2cpt(1gmt)