How to set a position of colorbox?

Question

I would like to place a colorbox under the x-axis under the xlabel. I means it should start under the 0 and end under the 22.

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

Thank you

Answer 1

You can use the coordinate system graph:

set bmargin 8
set colorbox horiz user origin graph 0,screen .08 size graph 1,screen .04
plot x w l lc pal