I note that ?min actually contains a relevant example:
plot(x, pmin(cH, pmax(-cH, x)), type='b', main= "Huber's function")
^^^^^^^^^^^^^^^^^^^^^^
It's always worth timing things. The timing tests below are the best
of several repetitions, to avoid worries about things like paging and GC.
Make a data frame with 10 variables and 2000 cases.
> m <- matrix(rnorm(10*2000), ncol=10)
> colnames(m) <- LETTERS[1:10]
> z <- as.data.frame(m)
See how long it takes to just make a copy of z.
> system.time(w <- z+0)
[1] 0.08 0.01 0.16 0.00 0.00
See how long pmax(pmin(...)...) takes.
> system.time(w <- pmax(pmin(z, 1), 0))
[1] 0.08 0.01 0.16 0.00 0.00
See how long the z[z < 0] <- 0; z[z > 1] <- 1 trick takes.
> system.time({ w <- z; w[w < 0] <- 0; w[w > 1] <- 1 })
[1] 0.23 0.01 0.31 0.00 0.00
______________________________________________
[EMAIL PROTECTED] mailing list
https://www.stat.math.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
