Re: [R] column permutation of sparse matrix

2011-12-22 Thread khai
Sorry. I erred somewhere in making the original M1 matrix using sampling call in the spMatrix function. I still don't really understand why the matrix values do not match exactly with M1@x. If I regenerate M1 this way... i=c(1:5,5:1) j=c(1:5,2:6) x=rnorm(10,2) M1 -

Re: [R] column permutation of sparse matrix

2011-12-21 Thread cberry
Douglas Bates ba...@stat.wisc.edu writes: On Tue, Dec 20, 2011 at 8:20 AM, Jean V Adams jvad...@usgs.gov wrote: Hi Jean, khai wrote on 12/19/2011 11:26:55 PM: Hi, I'm very new to working with sparse matrices and would like to know how I can column permute a sparse matrix. Here is a

Re: [R] column permutation of sparse matrix

2011-12-20 Thread Jean V Adams
khai wrote on 12/19/2011 11:26:55 PM: Hi, I'm very new to working with sparse matrices and would like to know how I can column permute a sparse matrix. Here is a small example: M1 - spMatrix(nrow=5,ncol=6,i=sample(5,15,replace=TRUE),j=sample(6,

Re: [R] column permutation of sparse matrix

2011-12-20 Thread Douglas Bates
On Tue, Dec 20, 2011 at 8:20 AM, Jean V Adams jvad...@usgs.gov wrote: Hi Jean, khai wrote on 12/19/2011 11:26:55 PM: Hi, I'm very new to working with sparse matrices and would like to know how I can column permute a sparse matrix. Here is a small example: M1 -

Re: [R] column permutation of sparse matrix

2011-12-20 Thread khai
Thanks very much for responses. The 2 suggestions each do a part of what I want. Jean's proposal permutes nonzero elements within each row but shifts the location of the nonzero element around in the j slot of each i row. And Douglas's idea keeps the second part but permutes the entire x slot

Re: [R] column permutation of sparse matrix

2011-12-20 Thread Jean V Adams
khai wrote on 12/20/2011 01:24:10 PM: Thanks very much for responses. The 2 suggestions each do a part of what I want. Jean's proposal permutes nonzero elements within each row but shifts the location of the nonzero element around in the j slot of each i row. And Douglas's idea keeps the

[R] column permutation of sparse matrix

2011-12-19 Thread khai
Hi, I'm very new to working with sparse matrices and would like to know how I can column permute a sparse matrix. Here is a small example: M1 - spMatrix(nrow=5,ncol=6,i=sample(5,15,replace=TRUE),j=sample(6,15,replace=TRUE),x=round_any(rnorm(15,2),0.001)) M1 5 x 6 sparse Matrix of class