Hi, I have two questions on using the ff package and wonder if anyone who used ff can share some thoughts.
I need to save a matrix as a memory-mapped file and load it back later. To save the matrix, I use mat = matrix(1:20, 4, 5) matFF = ff(mat, dim=dim(mat), filename="~/a.mat", overwrite=TRUE, dimnames = dimnames(mat)) To load it back, I use matFF2 = ff(vmode = "double", dim= ???, filename="~/a.mat", overwrite=F) However, I don't always know the dimension when loading the matrix back. If I miss the dim attributes, ff will return it as vector. Is there a way to load the matrix without specifying the dimension? The second question is that the matrix may grow in terms of the number of rows. I would like to synchronize the change to the memory-mapped file. Is there an efficient way to do this? Thanks Jeff ______________________________________________ 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.
