Robin Hankin wrote: > The error is given because after B[[1]] <- a, the variable B is > just a scalar and > not a matrix (why is this?) >
Because [[i]] indexes more general vectors, and if you do B[[1]] when B is NULL, R doesnt know if you want B to be a list or a simple vector. If you initialise B as an empty list then R knows: > B=list() > B list() > B[[1]]=b > B [[1]] [,1] [1,] 1 Barry ______________________________________________ R-help@stat.math.ethz.ch 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.