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Dataplot Reference Manual The graphics devices that Dataplot supports vary widely in the degree to which they support color. However, for the sake of device independence, all devices will recognize the same set of color names and color indices. If a given device does not support a requested color, DATAPLOT maps it to the closest available supported color (closest is somewhat arbitrary, although we tried to be reasonably consistent). Dataplot adopted its color scheme from Release 3 of X11 with a few additions from Release 4. It also uses the RGB values from Release 4 for those devices that support direct RGB specification. Although these values should be reasonably robust, different devices will generate different colors from them. Note 2020/11
Note 2020/11
Dataplot still supports a number of devices that do not provide full RGB color support. To handle this, Dataplot first checks if the device has full RGB color support. If so, Dataplot uses the settings from the RGB COLOR command (if given). If the device does not support full RGB colors or if no RGB COLOR command was issued, then the setting from the COLOR command is used. Dataplot does not provide any built-in templates for RGB color schemes. However, the following website provides 165 different RGB color schemes developed by Cynthia Brewer (you can download an Excel file that contains the schemes).
Numerous other RGB color templates are available. A discussion of color schemes is given by Paul Tol is available at
The following is the list of colors that DATAPLOT recognizes. Only the first 4 characters of the color name are significant and colors can also be specified by an index.
In addition, gray scale can be specified with the following scheme:
Gray scale values can also be specified with negative indices (that is, -1 through -100). Devices that do not support gray scale will map gray scale colors to either black or white. These are primarily older essentially obsolete devices. Penplotters no longer automatically map an index to the corresponding slot. Dataplot assumes the following slot to color mapping:
You can use the <HPGL/CALCOMP/ZETA> PEN MAP command to specify a different slot to color mapping for HP-GL, Calcomp, and Zeta plotters respectively. The following command shows the available colors.
The following commands show the colors available on the various color devices that DATAPLOT supports. That is, they show the color you actually get with the requested DATAPLOT color for that device.
SHOW COLORS TEKT 4662 SHOW COLORS TEKT 4027 SHOW COLORS HP 2622 SHOW COLORS CALCOMP SHOW COLORS ZETA SHOW COLORS CGM SHOW COLORS GENERAL SHOW COLORS SUN SHOW COLORS REGIS SHOW COLORS POSTSCRIPT SHOW COLORS X11 SHOW COLORS PC For some color display terminals (e.g., Tektronix 4105/7/9/15), the color can be altered locally after the plot has been generated on the screen. This gives the analyst a "second chance" if the original color choices do not mix well. Finally, be wary of the idiosyncracies of color hardcopy devices. They rarely capture the same color hues as on the screen (e.g., the Tektronix 4662 ink jet plotter maps a brilliant blue on the 4105/7/9/15 screen into a drab purple on the hardcopy). Also note that it is common for color hardcopies to map screen white into hardcopy black and vice versa. Note that the Postscript device is set to black and white by default. To activate color for Postscript devices, do the following:
DEVICE 2 COLOR ON Note that the order of these commands is relevant. Alternatively, you can specify that Postscript devices should be color be default by entering the command (before the DEVICE 2 POSTSCRIPT command)
Date created: 11/19/2020 |
Last updated: 02/14/2024 Please email comments on this WWW page to alan.heckert@nist.gov. |