[R] carpet plots

[Joseph Clark]

These "carpet plots" are also called "heat maps" and there's a current thread with the subject line "Heat Maps" in which I've given a couple of examples of code for them.  The R function image() is very easy to use:

 

image( x=(x values), y=(y values), z=(matrix of z values with x rows and y columns), col=(vector of colors), breaks=(vector of break points, one more than colors) )

 

What I'd like to know is: does anyone know how to easily create a legend/key to the color gradients, like the one in the right margin of Mueller's first example: (http://www.johannes-hopf.de/wordpress/wp-content/uploads/2009/12/Zufall-300x225.png)?


// joseph w. clark , phd candidate
\\ usc marshall school of business


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> Date: Mon, 2 Jul 2012 20:05:12 +0200
> From: mueller.eisborn at googlemail.com
> To: r-help at r-project.org
> Subject: [R] carpet plots
>
> Hi all,
> I wonder why there is so little software for carpet plots (german:
> Rasterdiagramm) (Three dimensional plot (x, y, z), the 3rd dimension
> (z) symbolized by colourgradients). Besides from one or the other non
> free software I only found an OpenOffice macro, a combination of
> Gnuplot and Excel (an Excel macro calling gnuplot)
> (http://www.johannes-hopf.de/2009/12/carpet-plot-version-1-3/9 and
> Quikgrid (http://www.galiander.ca/quikgrid/) which I use for
> bathymetric maps.
>
> Though I use one or two R scripts I have no deeper knowledge. Because
> I think "That's a thing R can do!", I suppose, there are scripts for
> this purpose. Perhaps one of you knows such a script. I would be very
> grateful if you could point me to some information on this subject.
>
> Richard
>
> --
> Richard Müller . Am Spring 9 . D-58802 Balve
> www.oeko-sorpe.de
>
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