Hi Lei,
one way to do this is the following:
mat <- matrix(rnorm(4*6), 4, 6)
ind <- c(3, 2, 4, 5)
mat[rep(seq_along(ind), ind), ]
I hope it helps.
Best,
Dimitris
Lei Liu wrote:
Hi there,
I have a question on manipulating a matrix. Say I have a matrix A with 3
rows. I want to generate a new matrix B with 3 duplicates of the first
row of A, 2 duplicates of the second row, and 4 duplicates of the third
row. So B is a matrix with 9 rows. Or more general, I want to generate
(3, 2, 4, 5) duplicates of rows 1-4 of a matrix with 4 rows. Is there a
simple function to do it? Thanks a lot!
Lei
______________________________________________
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.
--
Dimitris Rizopoulos
Assistant Professor
Department of Biostatistics
Erasmus University Medical Center
Address: PO Box 2040, 3000 CA Rotterdam, the Netherlands
Tel: +31/(0)10/7043478
Fax: +31/(0)10/7043014
______________________________________________
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.
