sock:colour <double> <double> <double> <double>

A set of sock:colour lines defines an RGB path for colourising the Sock Diagram, p..

parameters:

• red channel ($0...255$)
• green channel ($0...255$)
• blue channel ($0...255$)
• scale

For the linear colour model selected by the keyword sock:colmodel:lin, the scale parameter refers directly to sock significance. If the rank colour model is selected (sock:colmodel:rank), it refers to a fractile of sock significance on the interval $\left[0,1\right]$.