Hi,
I am trying to get the indices of non-zero entries of a sparse matrix in R
s r d
1 1089 3772 1
2 1109 190 1
3 1109 2460 1
4 1109 3071 1
5 1109 3618 1
6 1109 38 1
I found that the following can create a sparse matrix,
library(Matrix)
Y <- sparseMatrix(s,r,x=d)
but have not idea and did not find online how to convert a sparse
matrix back to three columns efficiently, i.e. get the indices of
non-zero entries of a sparse matrix.
In matlab, the find function can do this efficiently, I am wondering
is there a similar one in R?
Please advice. Thanks!
--gang
______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
