Differently but alike, Rainbow may have + Engineering applications
not as RGB, rather for graphs and export data sets from discontinuous.
Electron is from unsourced MCD given as is [maybe not level 0.005].

Image Rainbow Colormap [RGB band].sm (29,93 KiB) scaricato 1122 volta(e).
Image Rainbow Colormap [Electron].sm (374,51 KiB) scaricato 1059 volta(e).