xycpt - Man Page
generate GMT colour palette table (cpt) files from column data.
Synopsis
xycpt [-b rgb] [-d] [-f rgb] [-h] [-n rgb] [-o file] [-r registration] [-u] [-v] [-V] [file]
Description
The xycpt program generates discrete or continuous cpt files from simple input describing sample values of the colour (or greyscale) range. The input consists of 1–4 columns. For 2 and 4 columns, the first column is interpreted as a (double) z value, for 1 and 3 the z value is taken implicitly. For 1 and 2 columns the final column will be taken as a greyscale value. For 3 and 4, the last 3 columns are taken as RGB values.
The program will read from stdin if a file is not specified as the final argument, and write to stdout if the -o option is not specified.
Options
In the following, all rgb specifications should be of the form red/green/blue where the colour components are integers in the range 0 to 255.
- -b, --background rgb
Set the background colour of the output.
- --backtrace-file path
Specify a file to which to write a formatted backtrace. The file will only be created if there is a backtrace created, typically when an error occurs.
- --backtrace-format format
Specify the format of the backtrace written to the files specified by --backtrace-file, one of plain, xml or json.
- -d, --discrete
Output a discrete cpt file, the default is continuous.
- -f, --foreground rgb
Set the foreground colour of the output.
- -h, --help
Brief help.
- -n, --nan rgb
Set the NaN (no data) colour of the output.
- -o, --output file
Write the output to file, rather than stdout.
- -r, --registration string
For discrete (using the -d option) conversion, specifies upper, middle or lower registration of the data value. For the upper and lower types the final (respectively the first) colour is omitted from the output; only the z value is used. For middle registration all the colours appear in the output.
- -u, --unit
Colour values are specified as floating point numbers in the range 0–1 rather than as integers in the range 0–255.
- -v, --verbose
Verbose operation.
- -V, --version
Version information.
Author
J.J. Green
See Also
GMT(1).