From: "Mulholland, Tom" <Tom.Mulholland at dpi.wa.gov.au>
To: "Asha Jayanthi" <ashajayanthi at hotmail.com>,<r-help at stat.math.ethz.ch>
Subject: RE: [R] 2d plotting and colours
Date: Thu, 31 Mar 2005 10:14:13 +0800
Since I was only concentrating on colour issues and not on your specific
problem I was just showing the possibilities.
Does this code help
n <- 5
par(mfrow = c(2,2))
palette("default")
barplot(1:25,col = 1:25)
palette(rainbow(n))
barplot(1:25,col = 1:25)
palette(rgb((0:15)/15, g=0,b=0, names=paste("red",0:15,sep=".")))
barplot(1:25,col = 1:25)
require(cluster)
x <- runif(100) * 8 + 2
cl <- kmeans(x, n)
palette(rainbow(n))
plot(x, col = cl$cluster)
abline(h = cl$centers, lty = 2,col = "grey" )
palette(palette()[order(cl$centers)])
points(x,col = cl$cluster,pch = 20,cex = 0.4)
However you may wish to choose your colours in a way that is different from
cl$cluster which is why I changed the palette before plotting the points.
You should see that they now are ordered from bottom to top of the last
plot.
You could also choose to create a vector with your colours and then use the
value in cl$cluster to select the colours
mycols <- rainbow(n)
plot(x,col = mycols[cl$cluster])
Tom
-----Original Message-----
From: Asha Jayanthi [mailto:ashajayanthi at hotmail.com]
Sent: Thursday, 31 March 2005 9:17 AM
To: r-help at stat.math.ethz.ch
Subject: RE: [R] 2d plotting and colours
Thank you very much.
the code
plot(x, col = s)
points(cl$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
you could try the package dichromat. (I think 2.1 will have
inbuilt)
Once you look through the help files associated with some of
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),
(cl <- kmeans(x, i, 20))
s <- c("tomato4", "turquoise", "slateblue", "wheat",
"peru", "pink")
# see at:
colors()
plot(x, col = s)
points(cl$centers, col = s, pch = 8, cex=2)
Best,
Matthias
Hi!
I am new to R just 3 days in it and i apologize if my
questions seem very
trivial and consumed your valuable time.
I am coding in perl and i stumbled upon R regarding
statistical graphs.
I tried the kmean clustering for a large matrix ,say > 150 *
150 . I tried
the example code given in the tutorial to perform 2d plot
# i ranges from 2 to 10
cl <- kmeans(x, i, 20)
plot(x, col = cl$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