Displaying 1 result from an estimated 1 matches for "p20368695".
2008 Nov 06
3
.C(..., DUP=FALSE) memory costs depending on input size?
...size dependent
latency? The only reason I can think of is that these vectors are being
copied along the way.
What follows is both the R and C code which I use only for testing and a
plot of both measurements with DUP=TRUE and DUP=FALSE:
(RED: DUP=FALSE, GREEN: DUP=TRUE)
http://www.nabble.com/file/p20368695/CandR.png
R code:
----------
# sequence from 512 to 2^23 with 2^17 stepsize
a <- seq(512, 2^23, 2^17)
# storage for wall time
h <- length(a); j <- length(a)
for (i in 1:length(a)) {
x <- as.double(1:a[i])
y <- as.double(x)
# system.time()[3] is (actual) wall time...