Examples

Examples:
     set cntrparam bspline
     set cntrparam points 7
     set cntrparam order 10

To select levels automatically, 5 if the level increment criteria are met:

     set cntrparam levels auto 5

To specify discrete levels at .1, .37, and .9:

     set cntrparam levels discrete .1,1/exp(1),.9

To specify levels from 0 to 4 with increment 1:

     set cntrparam levels incremental  0,1,4

To set the number of levels to 10 (changing an incremental end or possibly the number of auto levels):

     set cntrparam levels 10

To set the start and increment while retaining the number of levels:

     set cntrparam levels incremental 100,50

To define and use a customized block of contour linetypes

     set linetype 100 lc "red" dt '....'
     do for [L=101:199] {
         if (L%10 == 0) {
             set linetype L lc "black" dt solid lw 2
         } else {
             set linetype L lc "gray" dt solid lw 1
         }
     }
     set cntrparam firstlinetype 100
     set cntrparam sorted levels incremental 0, 1, 100

See also set contour (p. [*]) for control of where the contours are drawn, and set cntrlabel (p. [*]) for control of the format of the contour labels and linetypes.

See also http://www.gnuplot.info/demo/contours.htmlcontours demo (contours.dem)

and http://www.gnuplot.info/demo/discrete.htmlcontours with user defined levels demo (discrete.dem).