color box

The color scheme, i.e. the gradient of the smooth color with min_z and max_z values of pm3d's palette, is drawn in a color box unless unset colorbox.

      set colorbox
      set colorbox {
                 { vertical | horizontal } {{no}invert}
                 { default | user }
                 { origin x, y }
                 { size x, y }
                 { front | back }
                 { noborder | bdefault | border <linestyle> } {cbtics <linestyle>}
               }
      show colorbox
      unset colorbox

Color box position can be default or user. If the latter is specified the values as given with the origin and size subcommands are used. The box can be drawn after (front) or before (back) the graph or the surface.

The orientation of the color gradient can be switched by options vertical and horizontal.

origin x, y and size x, y are used only in combination with the user option. The x and y values are interpreted as screen coordinates by default, and this is the only legal option for 3D plots. 2D plots, including splot with set view map, allow any coordinate system to be specified. Try for example:

    set colorbox horiz user origin .1,.02 size .8,.04

which will draw a horizontal gradient somewhere at the bottom of the graph.

border turns the border on (this is the default). noborder turns the border off. If an positive integer argument is given after border, it is used as a line style tag which is used for drawing the border, e.g.:

    set style line 2604 linetype -1 linewidth .4
    set colorbox border 2604

will use line style 2604, a thin line with the default border color (-1) for drawing the border. bdefault (which is the default) will use the default border line style for drawing the border of the color box.

cbtics allows you to specify a line style for the colorbox tics (cbtics) different from the line style of the border.

The axis of the color box is called cb and it is controlled by means of the usual axes commands, i.e. set/unset/show with cbrange, [m]cbtics, format cb, grid [m]cb, cblabel, and perhaps even cbdata, [no]cbdtics, [no]cbmtics.

set colorbox without any parameter switches the position to default. unset colorbox resets the default parameters for the colorbox and switches the colorbox off.

See also help for set pm3d, set palette, and set style line.