Duncan Murdoch <[EMAIL PROTECTED]> writes:
> On 10/3/2006 4:59 PM, roger bos wrote:
> > Dear useRs,
> >
> > Trying to replace the diagonal of a matrix is not working for me. I
> > want a matrix with .6 on the diag and .4 elsewhere. The following
> > code looks like it should work--when I lookk
On 10/3/06, roger bos <[EMAIL PROTECTED]> wrote:
> Dear useRs,
>
> Trying to replace the diagonal of a matrix is not working for me. I
> want a matrix with .6 on the diag and .4 elsewhere. The following
> code looks like it should work--when I lookk at mps and idx they look
> how I want them too-
On Tue, 3 Oct 2006, Duncan Murdoch wrote:
> On 10/3/2006 4:59 PM, roger bos wrote:
>> Dear useRs,
>>
>> Trying to replace the diagonal of a matrix is not working for me. I
>> want a matrix with .6 on the diag and .4 elsewhere. The following
>> code looks like it should work--when I lookk at mps
On Tue, 2006-10-03 at 17:03 -0400, Duncan Murdoch wrote:
> On 10/3/2006 4:59 PM, roger bos wrote:
> > Dear useRs,
> >
> > Trying to replace the diagonal of a matrix is not working for me. I
> > want a matrix with .6 on the diag and .4 elsewhere. The following
> > code looks like it should work--
try:
> mps <- matrix(rep(.4, 3*3), nrow=3, byrow=TRUE)
> idx <- diag(3)
> mps
[,1] [,2] [,3]
[1,] 0.4 0.4 0.4
[2,] 0.4 0.4 0.4
[3,] 0.4 0.4 0.4
> idx
[,1] [,2] [,3]
[1,]100
[2,]010
[3,]001
> mps[idx == 1] <- rep(.6,3)
>
> mps
[,1] [,2] [,
You are indexing with numeric 0's and 1's, which will refer to only the
matrix element 1,1 (multiple times), cf:
> matrix(1:9,3)[diag(3)]
[1] 1 1 1
>
Try one of these:
> idx <- diag(3) > 0
> idx <- which(diag(3)>0)
> idx <- cbind(seq(len=n), seq(len=n))
(For very large matrices, the third
On 10/3/2006 4:59 PM, roger bos wrote:
> Dear useRs,
>
> Trying to replace the diagonal of a matrix is not working for me. I
> want a matrix with .6 on the diag and .4 elsewhere. The following
> code looks like it should work--when I lookk at mps and idx they look
> how I want them too--but it o
Dear useRs,
Trying to replace the diagonal of a matrix is not working for me. I
want a matrix with .6 on the diag and .4 elsewhere. The following
code looks like it should work--when I lookk at mps and idx they look
how I want them too--but it only replaces the first element, not each
element on
