[R] 2d plotting and colours

[Asha Jayanthi]

Thank you very much.

the code
plot(x, col = s)
points(cl$centers, col = s, pch = 8, cex=2)

does not plot the points according to the group colors. The plots are used 
to identify the groups by colors

That could be done by

plot(x, col = cl$cluster)

This means that we need to set the default colours , say col = cl$cluster = 
a set of group numbers say 1...10 should produce 10 distinct colours points 
grouped by colour.

how to do this when you have more than 8 group colours to plot

>From: "Mulholland, Tom" <Tom.Mulholland at dpi.wa.gov.au>
>To: <r-help at stat.math.ethz.ch>,"Asha Jayanthi" <ashajayanthi at hotmail.com>
>Subject: RE: [R] 2d plotting and colours
>Date: Wed, 30 Mar 2005 15:59:46 +0800
>
>And getting back to your question about the palette
>
>there are a lot of ways to do this
>
>assuming you have just started a session
>
>palette()
># will give
>#[1] "black"   "red"     "green3"  "blue"    "cyan"
>#[6] "magenta" "yellow"  "gray"
>
>palette(rainbow(24))  # There's also 'heat.colors' & 'topo.colors'
>palette()
>
># [1] "red"         "#FF4000"     "#FF8000"
># [4] "#FFBF00"     "yellow"      "#BFFF00"
># [7] "#80FF00"     "#40FF00"     "green"
>#[10] "#00FF40"     "#00FF80"     "#00FFBF"
>#[13] "cyan"        "deepskyblue" "#0080FF"
>#[16] "#0040FF"     "blue"        "#4000FF"
>#[19] "#8000FF"     "#BF00FF"     "magenta"
>#[22] "#FF00BF"     "#FF0080"     "#FF0040"
>
>palette(rgb((0:15)/15, g=0,b=0, names=paste("red",0:15,sep=".")))
>palette()
># [1] "black"   "#110000" "#220000" "#330000" "#440000"
># [6] "#550000" "#660000" "#770000" "#880000" "#990000"
>#[11] "#AA0000" "#BB0000" "#CC0000" "#DD0000" "red2"
>#[16] "red"
>
>If you are looking to use colours that take account of colour blindness
>you could try the package dichromat. (I think 2.1 will have some of this 
>inbuilt)
>
>Once you look through the help files associated with some of these options 
>you
>will find the way that best suits your method of working.
>
>Tom
>
>
>
>
>
>
> > -----Original Message-----
> > From: Uwe Ligges [mailto:ligges at statistik.uni-dortmund.de]
> > Sent: Wednesday, 30 March 2005 3:18 PM
> > To: TEMPL Matthias
> > Cc: r-help at stat.math.ethz.ch; Asha Jayanthi
> > Subject: Re: [R] 2d plotting and colours
> >
> >
> > TEMPL Matthias wrote:
> >
> > > Hi!
> > >
> > > There are more than 8 colors.
> >
> > Yes, e.g. for rgb space there are 16777216, see ?rgb.
> >
> > Uwe Ligges
> >
> >
> >
> > > x <- rbind(matrix(rnorm(100, sd = 0.3), ncol = 2),
> > >                 matrix(rnorm(100, mean = 1, sd = 0.3), ncol = 2))
> > >
> > > (cl <- kmeans(x, i, 20))
> > >
> > > s <- c("tomato4", "turquoise", "slateblue", "wheat",
> > "snow", "skyblue",
> > > "peru", "pink")
> > > # see at:
> > > colors()
> > >
> > > plot(x, col = s)
> > >
> > > points(cl$centers, col = s, pch = 8, cex=2)
> > >
> > >
> > > Best,
> > > Matthias
> > >
> > >
> > >
> > >
> > >
> > >>Hi!
> > >>
> > >>I am new to R just 3 days in it and i apologize if my
> > >>questions seem very
> > >>trivial and consumed your valuable time.
> > >>
> > >>I am coding in perl and i stumbled upon R regarding plotting good
> > >>statistical graphs.
> > >>
> > >>I tried the kmean clustering for a large matrix ,say > 150 *
> > >>150 . I tried
> > >>the example code given in the tutorial to perform 2d plot
> > >>
> > >># i ranges from 2 to 10
> > >>cl <- kmeans(x, i, 20)
> > >>plot(x, col = cl$cluster)
> > >>points(cl$centers, col = 1:i )
> > >>
> > >>I see that there are only 8 colours defined , namely
> > >>black,red,green,blue,cyan,magenta,yello,gray.
> > >>
> > >>How should i set my colour preferences to obtain my palette
> > >>of colours? I
> > >>checked in the totorial which talks about R.colors and
> > >>palatte , but i
> > >>failed to understand how to set it.
> > >>
> > >>Thank You
> > >>
> > >>Asha
> > >>
> > >>