SHOW allow to produce Publication quality display of channel maps. Two control variables may be useful for this, SHOW_NX and SHOW_INTER. The GreG character type (SET FONT SIMPLEX or DUPLEX) and size can also be adjusted.
SHOW_NX indicates the number of columns (boxes along the X axis) to be used, the number of row being adjusted accordingly. When SHOW_NX is non zero, the Header panel is not displayed.
SHOW_INTER indicates the spacing between boxes (default is 0).