Entering edit mode
@nathan-s-watson-haigh-2987
Last seen 11.2 years ago
I have what I think should be really obvious, but seem to keep banging
my
head against a wall....ouch!
I want generate a heatplot for a set of genes from a contrast used in
my
limma analysis. However, I want to limit the heatplot to only those
arrays
used in the contrast. So I thought I'd be able to use the contrast and
design matrix to do just that. However, I'm having problems.....
My design matrix:
> design
H.N.N L.N.N H.Y.N L.Y.N H.Y.Y L.Y.Y
1 1 0 0 0 0 0
2 1 0 0 0 0 0
3 1 0 0 0 0 0
4 0 1 0 0 0 0
5 0 1 0 0 0 0
6 0 1 0 0 0 0
7 0 0 1 0 0 0
8 0 0 1 0 0 0
9 0 0 1 0 0 0
10 0 0 0 1 0 0
11 0 0 0 1 0 0
12 0 0 0 1 0 0
13 0 0 0 0 1 0
14 0 0 0 0 1 0
15 0 0 0 0 1 0
16 0 0 0 0 0 1
17 0 0 0 0 0 1
18 0 0 0 0 0 1
attr(,"assign")
[1] 1 1 1 1 1 1
attr(,"contrasts")
attr(,"contrasts")$TG
[1] "contr.treatment"
My contrast matrix:
> cont.matrix
Contrasts
Levels Helin_Acclimation Helin_Freezing Leitrim_Acclimation
Leitrim_Freezing
H.N.N -1 0 0
0
L.N.N 0 0 -1
0
H.Y.N 1 -1 0
0
L.Y.N 0 0 1
-1
H.Y.Y 0 1 0
0
L.Y.Y 0 0 0
1
Contrasts
Levels Acclimation Freezing Diff_Acclimation Diff_Freezing Population
H.N.N -1 0 1 0 -1
L.N.N -1 0 -1 0 1
H.Y.N 1 -1 -1 1 -1
L.Y.N 1 -1 1 -1 1
H.Y.Y 0 1 0 -1 -1
L.Y.Y 0 1 0 1 1
So I want to do this in a loop for all the contrasts I made:
for (mycoef in colnames(cont.matrix)) {
pval.max <- 0.05
maxheatplot.row <- 100
# get stats for this coef
TT <- topTable(fit2, adjust.method="BH", coef=mycoef, n=nrow(fit2))
# Just use those with an adj.p-value of < pval.max
TT <- TT[which(TT$adj.P.Val < pval.max),]
# make a heatplot for for the selected genes and include only those
arrays
used in the contrast
if (nrow(TT) > 1) {
heatplot.rows <- if(nrow(TT) > maxheatplot.row) { maxheatplot.row }
else {
nrow(TT) }
# index of those genes to include in the heatplot
index <- as.numeric(row.names(TT[c(1:heatplot.rows),]))
# Use the Contrast and design matrix to identify the arrays used in
the
contast
arrays <- which(design[,labels(which(cont.matrix[,mycoef] != 0))]
!=0)
png(file = paste("HP_", gsub(":", "_", mycoef), ".png", sep=""),
type =
"cairo1", width=10, height=10, units="in", res=300)
heatplot(eSet[index,arrays], labCol=sampleNames(eSet)[arrays],
labRow=TT$Symbol, margins=c(10,10), dend="row")
dev.off()
}
}
In the section dealing with creating the heatplot, the following code
pulls
out a subset of the design matrix:
> design[,labels(which(cont.matrix[,mycoef] != 0))]
H.N.N H.Y.N
1 1 0
2 1 0
3 1 0
4 0 0
5 0 0
6 0 0
7 0 1
8 0 1
9 0 1
10 0 0
11 0 0
12 0 0
13 0 0
14 0 0
15 0 0
16 0 0
17 0 0
18 0 0
I now want to pull out the row names which have a non-zero value in
any one
of the columns......can anyone help??
Cheers,
Nathan
--------------------------------------------------------
Dr. Nathan S. Watson-Haigh
OCE Post Doctoral Fellow
CSIRO Livestock Industries
Queensland Bioscience Precinct
St Lucia, QLD 4067
Australia
Tel: +61 (0)7 3214 2922
Fax: +61 (0)7 3214 2900
Web: <http: www.csiro.au="" people="" nathan.watson-haigh.html="">
http://www.csiro.au/people/Nathan.Watson-Haigh.html
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