National Aeronautics and Space Administration

Problems and Workarounds

The CIAO initialization script resets the $XANADU environmental variable needed by ximage. By initializing CIAO before HEASOFT this problem can be avoided.

On TrueColor displays, the File/Screen Grab... option of the /xtk device generates a bad image

On displays with color capability greater than 8-bit, the image created by the xwd screen dump utility is not completely compatible with xv. A miscolored image or a completely flat or strangely patterned image may result. The workaround is to use the ImageMagick convert option instead of the xv option. If ImageMagick is not available, the pgplot.xwd file in the current directory may be opened and cropped manually in an image editor of your choice.

Color tables don't change on TrueColor displays

This isn't a bug, but rather a technical difference between display types. The ability to change the color table of an already displayed image is exclusive to PseudoColor displays (i.e. 8 bit). To change color tables with a TrueColor display (i.e. 16 or 24 bit), the change must be made with the CCT/SET command before the image is drawn.

Can't quote qualifier value with trailing spaces

The Tcl parser has a problem with commands of the form: label cur text="trailing spaces " Use curly braces around the entire qualifier to workaround this parser problem: label cur {text=trailing spaces }

On Linux, text filenames beginning with a tilde (e.g. ~/out/excess.txt) are not found

Filename completion in XIMAGE provides a workaround. Create or edit a file named ~/.inputrc to contain the line:

set expand-tilde on

Whenever you complete a filename, the tilde will be expanded to its full path. Note: thanks to CFITSIO, however, FITS filenames may use tildes.