Hi, I am running the examples in page 70 of the ff package document, but it failed with the following error > cat("let's create some ff objects\n") let's create some ff objects > n <- 8e3 > a <- ff(sample(n, n, TRUE), vmode="integer", length=n, filename="d:/tmp/a.ff") > b <- ff(sample(255, n, TRUE), vmode="ubyte", length=n, filename="d:/tmp/b.ff") > x <- ff(sample(255, n, TRUE), vmode="ubyte", length=n, filename="d:/tmp/x.ff") > y <- ff(sample(255, n, TRUE), vmode="ubyte", length=n, filename="d:/tmp/y.ff") > z <- ff(sample(255, n, TRUE), vmode="ubyte", length=n, filename="d:/tmp/z.ff") > df <- ffdf(x=x, y=y, z=z) > rm(x,y,z) > cat("save some of them with shorter relative pathnames ...\n") save some of them with shorter relative pathnames ... > ffsave(a, b, file="d:/tmp/y", rootpath="d:/tmp") Error in system(cmd, input = list, intern = TRUE) : 'zip' not found > str(ffinfo("d:/tmp/y")) Error in system(cmd, intern = TRUE) : 'unzip' not found
Does it mean I have to install some special softwares for zip and unzip operation. Another question is whether ff always create physical files for vectors, I found when a ff ffdf object is created, the number of physical files created is eaqual to the number of data frame columns. Xiaobo.Gu ______________________________________________ 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.