On Tue, 2007-07-31 at 11:47 -0700, yuvika wrote:
> Hello,
>
> Thanks for the immediate help. However, I have a question for you.
> let's say the matrix looks like this
>
> name a1 a2 b1 b2 c1 c2
> 04 2 7 8 1 2
> 03 6 9 2
On Tue, 2007-07-31 at 10:35 -0700, yuvika wrote:
> Hello all,
>
> I have a matrix whose column names look like
>
> a1 a2 b1 b2 b3 c1 c2
> 1 23713 2
> 4 67814 3
>
> Now, I can have any number of a's. not just two as shown above and
>
yuvika wrote:
> Hello all,
>
> I have a matrix whose column names look like
>
> a1 a2 b1 b2 b3 c1 c2
> 1 23713 2
> 4 67814 3
>
> Now, I can have any number of a's. not just two as shown above and same
> goes for b's and c's. I nee
Sorry. There was a mistake in my previous code. Please disregard it
and use the following:
> r1=c(1,2,3,7,1,3,2)
> r2=c(4,5,7,8,1,4,3)
> test=matrix(c(r1,r2),nrow=2,ncol=7,byrow=TRUE)
> colnames(test)<-c("a1","a2","b1","b2","b3","c1","c2")
> test
[,1] [,2] [,3] [,4] [,5] [,6] [,7]
[1
You can use the grep function to obtain the column indices matching
your specified criteria. For example,
> r1<-c(1,2,3,7,1,3,2)
> r2<-c(4,5,7,8,1,4,3)
> test<-matrix(c(r1,r2),byrow=TRUE)
> colnames(test)<-c("a1","a2","b1","b2","b3","c1","c2")
> test
a1 a2 b1 b2 b3 c1 c2
[1,] 1 2
