[R] Howto Compute Pairwise Similarity/Correlation Matrix from a Data Frame
Gundala Viswanath
gundalav at gmail.com
Wed Jun 18 08:55:48 CEST 2008
Hi,
I have the following 5 vectors. I wish to compute
the pairwise Pearson Correlation matrix with this data.frame.
Is there a compact way to do it?
At the end I hope to create a heatmap out of this correlation matrix.
__BEGIN__
> data <- read.table("mydata.txt")
> print(data)
V1 V2 V3 V4 V5 V6 V7 V8 V9
1 42.3 53.2 76.4 78.8 83.6 91.3 92.2 105.8 109.6
2 6.8 9.7 12.7 13.1 14.6 16.3 17.2 17.9 18.1
3 10.6 21.5 34.4 38.2 38.8 50.0 60.7 64.0 64.3
4 215.3 227.4 227.7 245.0 257.2 260.0 269.8 287.3 340.2
5 4.1 4.2 4.6 6.4 6.8 6.9 16.9 17.6 23.3
__END__
Currently I am stuck in constructing the very matrix itself from
double loop.
__BEGIN__
data <- read.table("GDS596_part1.txt")
nofrow <- nrow(data)
for (rwx in 1:nofrow) {
print(data[rwx,])
for (rwy in 1:nofrow) {
print(data[rwy,])
thecor <- cor(data[rwx,],data[rwy.], method="pearson")
# not sure how to proceed from here.
}
}
__END__
Please advice.
- Gundala Viswanath
Jakarta - Indonesia
More information about the R-help
mailing list