[Rd] WRONG mailing list - Re: question in value-based color in image()

Martin Maechler maechler at stat.math.ethz.ch
Tue Sep 16 11:58:54 CEST 2008


Please do use R-help, (not R-devel)
for such questions.

>>>>> "M" == M  <glycob at gmail.com>
>>>>>     on Mon, 15 Sep 2008 22:42:22 -0400 writes:

    M> Hello, I have a matrix with value varying from -1 to 1.
    M> I hope to use scaled color based on its value to produce
    M> an image of this matrix.

    M> Suppose I hope to label those data in [-1,-0.5] with
    M> blue, label those [-0.5,0.8] with light blue (tone is
    M> proportional to its value) and label those [0.8,1] with
    M> white.

    M> How can I use image() and rgb() to achieve this?  It
    M> would be great if I can have a color scale legend, too.

    M> TIA, Chris

    M> 	[[alternative HTML version deleted]]



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