Displaying 2 results from an estimated 2 matches for "row_sums".
2010 Dec 06
1
Sparse matrix performance question
I have a very sparse square matrix which is < 20K rows & columns and I am
trying to row standardize the matrix for the rows that have non-missing
value as follows:
row_sums <- rowSums(M,na.rm=TRUE)
nonzero_idxs <- which(row_sums>0)
nonzero_M <- M[nonzero_idxs,]/row_sums[nonzero_idxs]
M[nonzero_idxs,] <- nonzero_M
Each line completes well under a second except the last line which takes
well over 10 seconds which is simply assigning the sub-matrix of row...
2009 May 27
3
Neural Network resource
Hi All,
I am trying to learn Neural Networks. I found that R has packages which can help build Neural Nets - the popular one being AMORE package. Is there any book / resource available which guides us in this subject using the AMORE package?
Any help will be much appreciated.
Thanks,
Indrajit