I've just found an annoyance with the behaviour of %/% which, BTW, violated the sacred rule that for all a, and non-zero b:
a = b * (a %/% b) + a %% b Namely, that Inf %/% n is not Inf, but NaN. Why is this so? It's an annoyance, because in expressions like: big.vector.1[a, b, c] <- big.vector.2[a, b, c] %/% n we must treat Inf and -Inf as exceptions, when a simple division does not have these exceptions BTW, I treated this exception the way Grace Hopper would be proud of, namely, "it's easier to ask forgiveness than it is to get permission", but at the cost of memory: big.vector.1 <- big.vector.2 big.vector.1[a, b, c] <- big.vector.2[a, b, c] %/% n tst <- is.nan(big.vector.1) if (any(tst)) big.vector.1[tst] <- big.vector.2 Alberto Monteiro ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
