Sarah,
Here's a version using two nested loops:
rate_number = matrix(c(5, 15, 60, 15, 5, 0, 20, 60, 20,0, 10, 20, 40,
20, 10), nrow = 5, ncol = 3)
range_mat = matrix(c(6.25, 6.75, 7.25, 8.75, 9.25, 9.75, 8.5, 9, 9.5,
10.5, 11, 11.5, 4.25, 4.75, 5.25, 5.75, 6.25, 6.75), nrow = 6, ncol = 3)
set.seed(123)
res <- vector(mode = "list", length = NCOL(rate_number))
rateSum <- colSums(rate_number)
for(i in seq_len(NCOL(rate_number))) {
res[[i]] <- numeric(length = rateSum[i])
rates <- rate_number[,i]
rates <- rates[(want <- which(rates > 0))]
for(j in seq_along(rates)) {
if(j == 1) {
from <- 1
to <- rates[1]
} else {
from <- sum(rates[1:(j-1)]) + 1
to <- sum(rates[1:j])
}
res[[i]][from:to] <- runif(rates[j],
min = range_mat[want[j],i],
max = range_mat[want[j]+1, i])
}
}
str(res)
head(res)
Not the most elegant code but it works...
Most of the fiddling about in there is to work round the fact that you
have 0's in some cells of rate_number and I wanted to avoid
concatenating vectors to enlarge them, so allocate storage first.
HTH
G
On Fri, 2010-09-03 at 03:32 -0700, Sarah Sanchez wrote:
> Dear R helpers
>
> I have following dataset
>
> rate_number = matrix(c(5, 15, 60, 15, 5, 0, 20, 60, 20,0, 10, 20, 40, 20,
> 10), nrow = 5, ncol = 3)
>
> range_mat = matrix(c(6.25, 6.75, 7.25, 8.75, 9.25, 9.75, 8.5, 9, 9.5, 10.5,
> 11, 11.5, 4.25, 4.75, 5.25, 5.75, 6.25, 6.75), nrow = 6, ncol = 3)
>
> > rate_number
> [,1] [,2] [,3]
> [1,] 5 0 10
> [2,] 15 20 20
> [3,] 60 60 40
> [4,] 15 20 20
> [5,] 5 0 10
>
> > range_mat
> [,1] [,2] [,3]
> [1,] 6.25 8.5 4.25
> [2,] 6.75 9.0 4.75
> [3,] 7.25 9.5 5.25
> [4,] 8.75 10.5 5.75
> [5,] 9.25 11.0 6.25
> [6,] 9.75 11.5 6.75
>
> My problem is to generate random numbers in line with rate_number and using
> the range_mat. E.g.
>
> I need to generate (5, 15, 60, 15, 5 i.e. the first column of rate_number)
> uniform random numbers (using 1st column of range_mat) s.t the first 5
> numbers will be in the range (6.25 - 6.75), next 15 numbers should be in the
> range (6.75 to 7.25), next 60 numbers should be in the range (7.25 to 8.75),
> next 15 numbers in the range (8.75 to 9.25) and last 5 numbers in the range
> (9.25 to 9.75).
>
> Similarily, I need to generate (0, 20, 60, 20, 0 i.e. 2nd column of
> rate_number) uniform random numbers in the range (using 2nd column of
> range_mat) i.e. (8.5 to 9), (9 to 9.5), (9.5 to 10.5), (10.5 to 11), (11 to
> 11.5) respectively.
>
> I could have generated these random numbersIndividually using runif, but main
> problem is range_number could be anything i.e. there may be 50 rates but for
> each rate, no of rate combination will always be 5 i.e. rate_number will
> always have 5 rows only and also range_mat will always have 6 rows only.
>
> I tried writing loops and even tapply etc. but just can't get through.
>
> I sincerely request you to kindly guide me.
>
> Regards
>
> Sarah
>
>
>
>
>
>
>
> [[alternative HTML version deleted]]
>
> ______________________________________________
> 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.
--
%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%
Dr. Gavin Simpson [t] +44 (0)20 7679 0522
ECRC, UCL Geography, [f] +44 (0)20 7679 0565
Pearson Building, [e] gavin.simpsonATNOSPAMucl.ac.uk
Gower Street, London [w] http://www.ucl.ac.uk/~ucfagls/
UK. WC1E 6BT. [w] http://www.freshwaters.org.uk
%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%
______________________________________________
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.
