Here's one way. new.matrix <- my.matrix new.matrix[] <- with(my.df, my.value[match(my.matrix, my.id)])
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Milton Cezar Ribeiro Sent: Saturday, 24 November 2007 7:14 AM To: R-help Subject: [R] updating matrix from a dataframe Dear all, I have a matrix which values varying from 1 to 5. I also have a table with a column that match with matrix values (=my.id). my.matrix<-matrix(sample(1:5,100,replace=T),nc=10) image(my.matrix) my.df<-data.frame(cbind(my.id=1:5,my.value=c(0.1,0.3,0.2,0.9,1))) my.df How can I create a new matrix, where the values of this matrix is my.value when the value of my.matrix match with my.df$my.id I can do it in a for() looping, but my matrix are so big (2000 x 2000) and I need to it about 1,000 times. Thanks in advance, Miltinho para armazenamento! [[alternative HTML version deleted]] ______________________________________________ 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. ______________________________________________ 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.
