cptcont - Man Page

cptcont [-h] [-M] [-o path] [-p percent] [-v] [-V] [-z] [-Z] [-4] [-5] [-6] [path]

The cptcont program converts a (possibly) discontinuous colour palette in the input to a continuous palette in the output​. This is achieved by replacing the endpoints of segments at which a discontinuity occurs by their mean colour​.

The program will read from stdin if a file is not specified as the final argument, and write to stdout if the --output option is not specified​.

--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​.

--comments-read path

Read the comments from the specified path and add them to the output gradient​.

The format is simply a plain text multi-line document without any comment delimiters (those will be added by the program)​.

--comments-write path

Write the comments in the input to the specified path​.

--comments-retain

Use the comments in the input file as the comments for the output file​.

--comments-generate

Create a comment with summary data (the date of creation, name and version of the cptutils package) in the output file​.

-h,  --help

Brief help​.

--hinge value

Specify the z-value of the hinge in the cpt file​. If there is no hinge directive (i​.e​., a SOFT_HINGE or HARD_HINGE) in the input, then this option has no effect​.

When normalising (with the --z-normalise option), this gives the z-value in the input which is mapped to zero​. That z-value must be one of the stops in the input​.

When denormalising (with the --z-denormalise option), this gives the value in the output to which zero in the input is mapped​. This option can be viewed as the counterpart to the +hvalue appended to the -C option for the makecpt(1)​.

--hinge-active

If the input cpt has a SOFT_HINGE directive, then activate that hinge (resulting in independent scaling of the two halves of the gradient either side of the hinge)​.

If the input does not have such a directive, then this option has no effect​.

-M,  --midpoint

Split each input segment into two output segments with the colour at the common point being the colour of the original segment​. This gives a more faithful conversion of gradients with "corners", such as diverging gradients, albeit at the cost of larger files​.

-o,  --output path

Write the output to path, rather than stdout​.

-p,  --partial percentage

The endpoints are moved the specified pecentage towards the mean colour, so that a value of 100 (the default) moves the endpoints to the mean colour, 50 moves them half-way there, and so on​.

Negative values and values greater than 100 are permitted (these can give interesting effects, but are not really suitable for publication-quality plots)​.

-v,  --verbose

Verbose operation​.

-V,  --version

Version information​.

-z,  --z-normalise

Normalise the z-values in the cpt output into the range 0/1 (or to -1/1 if a hinge is present) and add a RANGE directive if not present in the input​. This is the form used in GMT master files​.

This option requires that output cpt version is at least 5​.

-Z,  --z-denormalise

Set the z-values in the cpt output into the range given by the RANGE directive, and remove that directive​. If there is no RANGE then this option does nothing​.

-4,  --gmt4

Use GMT 4 conventions when writing the cpt output: the colour-model code is uppercase, and the colours are separated by spaces​.

This is incompatible with the -5 and -6 options of course​.

At present this option is the default, but that will change at some point​. So specify this option if your use of the output depends on the GMT 4 layout (consumed by a custom parser, for example)​.

-5,  --gmt5

Use GMT 5 conventions when writing the cpt output: the colour-model code is lowercase, and the colours are separated by a solidus for RGB, CMYK, by a dash for HSV​.

This is incompatible with the -4 and -6 options of course​.

-6,  --gmt6

As the -5 option, but allows the HARD_HINGE and SOFT_HINGE directives in place of the explicit HINGE = directive​.

This is incompatible with the -4 and -5 options of course​.

Create an almost-continuous table:

cptcont -v -p 66 -o new​.cpt old​.cpt

J​.J​. Green