The LOADCT procedure loads one of 41 predefined IDL color tables. These color tables are defined in the file colors1.tbl (located in the main IDL directory) unless the FILE keyword is specified. The selected colortable is loaded into the COLORS common block as both the "current" and "original" colortable. If the current device has fewer than 256 colors, the color table data is interpolated to cover the number of colors in the device.

This routine is written in the IDL language. Its source code can be found in the file loadct.pro in the lib subdirectory of the IDL distribution.

Calling Sequence

LOADCT [, Table]



The number of the pre-defined color table to load, from 0 to 40. If this value is omitted, a menu of the available tables is printed and the user is prompted to enter a table number.



The first color index to use. LOADCT will use color indices from BOTTOM to BOTTOM+NCOLORS-1. The default is BOTTOM=0.


Set this keyword to the name of a colortable file to be used instead of the file colors1.tbl in the IDL directory. The procedure (page ) can be used to create and modify colortable files.


Set this keyword to a named variable in which the names of the color tables are returned as a string array. No changes are made to the color table.


The number of colors to use. The default is all available colors (this number is stored in the system variable !D.TABLE_SIZE).


If this keyword is set, the Color Table message is suppressed.

See Also