You haven't indicated what information you want to convey with this gradient.
You also are using arrays where you should be using vectors, usually stored in a data frame. Here is one way using the contributed package ggplot2: library(ggplot2) DF <- data.frame( V1=1:10, V2=11:20, C=21:30 ) p <- ggplot( DF, aes( x=V1, y=V2, colour=C ) ) + geom_line( size=2 ) + scale_colour_gradient( low="red", high="blue" ) print( p ) -- Sent from my phone. Please excuse my brevity. On February 4, 2017 12:19:14 PM PST, David Winsemius <dwinsem...@comcast.net> wrote: > >> On Feb 4, 2017, at 9:14 AM, Riyas MJ <riyasmj...@gmail.com> wrote: >> >> Hi all, >> >> I am a new user of R. I just did my first real program. >> I would like to know how to put a gradient (like rainbow() or >topo.colors, >> etc) to a* line* graph. >> >> Example: >> ar1=array(data=1:10,dim=9) >> ar2=array(data=11:20,dim=9) >> plot(ar1,ar2,type="l",col="red",lwd=3) >> >> Instead of a red color, I would like to make it in rainbow colors. >> Tried to do my own and tried searching but everywhere its about >giving >> gradient to point graph, not to a line graph. Please help, it is >needed for > >Install the plotrix package and look in its Index page for a function >name that has both `color` and `line` in its name. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.