[R] Matrix to "indexed" vector
Sean Davis
sdavis2 at mail.nih.gov
Tue Jan 11 13:35:40 CET 2005
I have a matrix that I want to turn into a transformed matrix that
includes the indices from the original matrix and the value. The
matrix is simply real-valued and is square (and large (8k x 8k)). I
want something that looks like (for the 3x3 case):
i j value
1 1 1.0
1 2 0.783432
1 3 -0.123482
2 1 0.783432
2 2 1.0
2 3 0.928374
and so on....
I can do this with for loops, but there is likely to be a better way
and for my own edification, I would like to see what others would do.
I am sinking the results to a file for loading into SQL database.
Thanks,
Sean
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