Displaying 4 results from an estimated 4 matches for "verstrichen".
2014 Mar 02
1
internal copying in R (soon to be released R-3.1.0
...ets sxpinfo_struct.named to 2. It even sets it to 2
if the argument to .Call was a never-named expression!?
> named(1:3)
[1] 2
And it seems to set it permanently, pure read-access can trigger
copy-on-modify:
> x <- integer(1e8)
> system.time(x[1]<-1L)
User System verstrichen
0 0 0
> system.time(x[1]<-2L)
User System verstrichen
0 0 0
having called .Call now leads to an unnecessary copy on the next assignment
> named(x)
[1] 2
> system.time(x[1]<-3L)
User System ve...
2012 Sep 19
3
effective way to return only the first argument of "which()"
Hi,
I was looking for a function like "which()" but only returns the first argument.
Compare:
x <- c(1,2,3,4,5,6)
y <- 4
which(x>y)
returns:
5,6
which(x>y)[1]
returns:
5
which(x>y)[1] is exactly what i need. I did use this but the dataset
is too big (~18 mio. Points).
That's why i need a more effective way to get the first element of a
vector which is
2012 May 02
6
Quickest way to make a large "empty" file on disk?
R-helpers:
What would be the absolute fastest way to make a large "empty" file (e.g.
filled with all zeroes) on disk, given a byte size and a given number
number of empty values. I know I can use writeBin, but the "object" in
this case may be far too large to store in main memory. I'm asking because
I'm going to use this file in conjunction with mmap to do parallel
2008 Oct 22
1
R 2.8.0 qqnorm produces error with object of class zoo?
Dear list-reader,
by running the following script:
library(zoo)
sessionInfo()
search()
packageDescription("zoo")
data(EuStockMarkets)
dax <- as.zoo(EuStockMarkets[1:10, "DAX"])
daxr <- diff(log(dax))
identical(as.vector(qnorm(daxr)), qnorm(coredata(daxr)))
qqnorm(coredata(daxr))
qqnorm(daxr)
qqnorm() produces an error:
> qqnorm(daxr)
Fehler in if (xi == xj) 0L