11.52.76 viewer
set viewer ( auto | <command> )
The set viewer command is used to select which external PostScript viewing application is used to display Pyxplot output on screen in the X11 terminals. If the option auto is selected, then either ghostview or ggv is used, if installed. Alternatively, any other application such as evince or okular can be selected by name, providing it is installed in within your shell’s search path or an absolute path is provided, as in the examples:
set viewer evince
set viewer /usr/bin/okular
Additional commandline switches may also be provided after the name of the application to be used, as in the example
set viewer gv --grayscale