Hello R Experts, I need a bit of help in using loop. I have a matrix onto which I need to use several functions. In a simplified form suppose my matrix is> mdat[,1] [,2] [,3] [,4] [,5] [1,] 1 2 3 4 5 [2,] 11 12 13 10 10 [3,] 2 3 4 5 6 [4,] 10 9 8 9 10 [5,] 5 6 7 8 4 And I have one vector> x[1] 14 15 10 11 18 Now suppose in simple form I want to create a matrix in which each col value will be divided with consecutive no from vector x. For example column 1 of new vector will be C1=mdat[,1]*100/x[1]> C1[1] 7.142857 78.571429 14.285714 71.428571 35.714286 Now how can I use the loop to have the complete vector at a time? I tried something like this, but in vain. for(i in 1:5) { Data=(mdat[,i]*100/x[i], add=T) } Any help will be really great. Thanks, Mitra [[alternative HTML version deleted]]
Hi,
?sweep
mdat <-
matrix(c(1,11,2,10,5,2,12,3,9,6,3,13,4,8,7,4,10,5,9,8,5,10,6,10,4),5,5)
x <- c(14,15,10,11,18)
sweep(mdat*100, 2, x, FUN='/')
[,1] [,2] [,3] [,4] [,5]
[1,] 7.142857 13.33333 30 36.36364 27.77778
[2,] 78.571429 80.00000 130 90.90909 55.55556
[3,] 14.285714 20.00000 40 45.45455 33.33333
[4,] 71.428571 60.00000 80 81.81818 55.55556
[5,] 35.714286 40.00000 70 72.72727 22.22222
Hope this helps,
Pascal
On 05/21/2013 04:16 PM, Suparna Mitra wrote:> Hello R Experts,
> I need a bit of help in using loop.
> I have a matrix onto which I need to use several functions.
>
> In a simplified form suppose my matrix is
>> mdat
> [,1] [,2] [,3] [,4] [,5]
> [1,] 1 2 3 4 5
> [2,] 11 12 13 10 10
> [3,] 2 3 4 5 6
> [4,] 10 9 8 9 10
> [5,] 5 6 7 8 4
>
> And I have one vector
>> x
> [1] 14 15 10 11 18
>
> Now suppose in simple form I want to create a matrix in which each col
> value will be divided with consecutive no from vector x. For example
>
> column 1 of new vector will be C1=mdat[,1]*100/x[1]
>
>> C1
> [1] 7.142857 78.571429 14.285714 71.428571 35.714286
>
> Now how can I use the loop to have the complete vector at a time?
> I tried something like this, but in vain.
> for(i in 1:5) {
> Data=(mdat[,i]*100/x[i], add=T)
> }
>
> Any help will be really great.
> Thanks,
> Mitra
>
> [[alternative HTML version deleted]]
>
> ______________________________________________
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> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
On 21-05-2013, at 09:16, Suparna Mitra <suparna.mitra.sm at gmail.com> wrote:> Hello R Experts, > I need a bit of help in using loop. > I have a matrix onto which I need to use several functions. > > In a simplified form suppose my matrix is >> mdat > [,1] [,2] [,3] [,4] [,5] > [1,] 1 2 3 4 5 > [2,] 11 12 13 10 10 > [3,] 2 3 4 5 6 > [4,] 10 9 8 9 10 > [5,] 5 6 7 8 4 > > And I have one vector >> x > [1] 14 15 10 11 18 > > Now suppose in simple form I want to create a matrix in which each col > value will be divided with consecutive no from vector x. For example > > column 1 of new vector will be C1=mdat[,1]*100/x[1] > >> C1 > [1] 7.142857 78.571429 14.285714 71.428571 35.714286 > > Now how can I use the loop to have the complete vector at a time? > I tried something like this, but in vain. > for(i in 1:5) { > Data=(mdat[,i]*100/x[i], add=T) > } >See this discussion: http://r.789695.n4.nabble.com/Divide-matrix-columns-by-different-numbers-td4666013.html Other possibilities taken from that thread mdat*100/rep(x,each=nrow(mdat)) 100*t(t(mdat)/x) Berend