.Rprofile

# http://stackoverflow.com/questions/1189759/expert-r-users-whats-in-your-rprofile
#set cran repo
r <- getOption("repos")             # hard code the US repo for CRAN
r["CRAN"] <- "http://cran.us.r-project.org"
options(repos = r)
rm(r)

#persistent RHistory
.Last <- function() {
        if (!any(commandArgs()=='--no-readline') && interactive()){
                require(utils)
                try(savehistory(Sys.getenv("R_HISTFILE")))
        }
}
#terminal width
#tryCatch(
  #{options(
      #width = as.integer(Sys.getenv("COLUMNS")))},
  #error = function(err) {
    #write("Can't get your terminal width. Put ``export COLUMNS'' in your \
           #.bashrc. Or something. Setting width to 120 chars",
           #stderr());
    #options(width=120)}
#)
#memory management
# improved list of objects
.ls.objects <- function (pos = 1, pattern, order.by,
                        decreasing=FALSE, head=FALSE, n=5) {
    napply <- function(names, fn) sapply(names, function(x)
                                         fn(get(x, pos = pos)))
    names <- ls(pos = pos, pattern = pattern)
    obj.class <- napply(names, function(x) as.character(class(x))[1])
    obj.mode <- napply(names, mode)
    obj.type <- ifelse(is.na(obj.class), obj.mode, obj.class)
    obj.prettysize <- napply(names, function(x) {
                           capture.output(print(object.size(x), units = "auto")) })
    obj.size <- napply(names, object.size)
    obj.dim <- t(napply(names, function(x)
                        as.numeric(dim(x))[1:2]))
    vec <- is.na(obj.dim)[, 1] & (obj.type != "function")
    obj.dim[vec, 1] <- napply(names, length)[vec]
    out <- data.frame(obj.type, obj.size, obj.prettysize, obj.dim)
    names(out) <- c("Type", "Size", "PrettySize", "Rows", "Columns")
    if (!missing(order.by))
        out <- out[order(out[[order.by]], decreasing=decreasing), ]
    if (head)
        out <- head(out, n)
    out
}

# shorthand
lsos <- function(..., n=10) {
    .ls.objects(..., order.by="Size", decreasing=TRUE, head=TRUE, n=n)
}
# aliases
s <- base::summary;
h <- utils::head;
n <- base::names;