It rather sounds like you might be designing a gauge display for a dashboard. If that's the case, I'd recommend checking out:
Information Dashboard Design: The Effective Visual Communication of Data Stephen Few http://www.amazon.com/dp/0596100167 as well as some of his online writings: http://www.perceptualedge.com/articles/dmreview/dashboard_design.pdf http://www.perceptualedge.com/articles/visual_business_intelligence/pervasive_hurdles_to_dd.pdf http://www.perceptualedge.com/blog/?p=102 Hadley On Fri, Aug 15, 2008 at 7:00 AM, Roger Leenders <[EMAIL PROTECTED]> wrote: > > R2.7.1, WinXP > > Hi, > > I have a polygon inside a circle as follows: > > radius <- 3 > x <- seq(-radius,radius,length=2000) > y <- sqrt(radius^2-x^2) > xx <- c(x,-x) > yy <- c(y,-y) > plot(xx,yy, xlim=c(-radius,radius),ylim=c(-radius,radius), type="l", > ylab="", xlab="", axes=F) > > radius <- 2.7 > x1 <- seq(-radius,radius,length=2000) > y1 <- sqrt(radius^2-x1^2) > radius <- 2.0 > x2 <- seq(radius,-radius,length=2000) > y2 <- sqrt(radius^2-x2^2) > > polygon(c(x1,x2),c(y1,y2)) > > (the graph much resembles a speed dial inside a car). > Now I want to fill the polygon with color, such that it starts on the left > with red and ends on the right with green, following the coloring of the > rainbow. > Preferably, the coloring should be "continuous", such that colors naturally > fade into each other. > I can draw the polygon as above, but I don't know how to do the coloring. It > is easy to give the polygon only one color (e.g. through > polygon(c(x1,x2),c(y1,y2), col="red")), but I need a way in which to color > the polygon such that the color moves through the color spectrum from red > (left) to green (right). > Can anyone help me to achieve this? > > Thanks, Roger > > ______________________________________________ > R-help@r-project.org mailing list > 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. > -- http://had.co.nz/ ______________________________________________ R-help@r-project.org mailing list 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.
