set cstyle style
Sets the contour linestyle. style options are:
0 - no contours 1 - solid 2 - long dash 3 - short dash 4 - long dash, short dash 5 - dotted 6 - dot dash 7 - dot dot dash
set cstyle is reset by entering clear or display.
set cstyle 0 will generate the following message:
"WARNING cstyle = 0 ; no lines will be plotted; I suggest 1
...". However, it may be used with set cmark for drawing a
'line' plot with marks at all the data points that are not connected
by a line.