R programming language resources › Forums › Graphing › adding labels to x,y points
- This topic has 2 replies, 2 voices, and was last updated 13 years, 7 months ago by
baumeist.
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- September 15, 2011 at 4:37 pm #335
baumeist
MemberHi,
I am new to R.I have a dataframe that I have assigned to the object “colon”.
> colon<-read.table("c:\\alon.txt",header=T,row.names=1) attach(colon) names(colon) It (i.e. colon) consists of 62 different columns (samples) or sets of data. Each of the 62 columns (titled norm1, norm2, norm3, etc) has 2000 different numbers (‘continuous’ values) within it. I have also assigned a name for each of the 2000 rows of the dataframe with a prefix (i.e. g1 …. g2000). > colon<-paste("g",c(1:nrow(colon)),sep="") I have plotted the first 20 values from two of the columns(samples). > x<-c(norm1[1:20]) > y<-c(norm2[1:20]) > plot(x,y,type=’n’,xlab=’x norm1 sample’,ylab=’y norm2 sample’,main=’Norm1 vs Norm2 – 20
genes’)> points(x,y,pch=15,col=’blue’)
Now I wish to assign labels to each point (above each point (i.e. pos=3) in the plot with “g1 to g20 corresponding to each row but I am having trouble with this step.
I have tried:
> text(x,y, label = row.names(colon[1:20]))
but nothing happens.
Any suggestions?
Thanks in advance
MABSeptember 21, 2011 at 5:11 pm #359bryan
ParticipantHi baumeist,
A couple of recommendations:
First, I would not use the attach command. It makes things a little more difficult in the long run than just using direct references to the variables (e.g., colon$norm1).
Second, when you do this
colon<-paste("g",c(1:nrow(colon)),sep="")
you're creating an object with the same name as your attached data object. That is potentially confusing and could cause problems. Better to create something with a different name.
However, I think your main problem is that you're using row.names() in the "labels = attribute" of the text() function when you don't need to. The "colon" object your creating is just a vector with no row.names attribute. Try dropping that and see if you get what you want.
October 6, 2011 at 5:17 pm #365baumeist
MemberThanks a lot, Bryan.
Mark
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