Try this if you want a matrix of functions:
> # define matrix of list()
> x <- vector('list', 25)
> dim(x) <- c(5,5)
> f.1 <- function(x) x * x
> x[[1,1]] <- f.1
> x[[2,2]] <- f.1
> # call the functions
> x[[2,2]](42)
[1] 1764
> x[[1,1]](3)
[1] 9
>
On Tue, Nov 6, 2012 at 6:01 AM, Jessica Streicher
<j.streic...@micromata.de> wrote:
> Not that i really understand what that shall do, but..
>
> why do you define 2 functions that do exactly the same?
> why do you want to make a matrix of functions instead of a matrix with the
> results of functions?
>
> On 06.11.2012, at 05:11, Aimee Kopolow wrote:
>
>> Hi all,
>>
>>
>> I have a matrix simulating migration in a spatial model. I want to be
>> able to define movement (the values of m1, m2 and m3) as only != 0
>> between adjacent patches and contingent on certain conditions as
>> defined in the function.
>>
>> Here is the code:
>>
>> WET<-function(t) {everglades$precipitation[t]} #simply reads
>> precipitation data from a csv, value is numeric
>>
>> AB<-function(WET,t) {ifelse(WET(t)>0, 0.0001, 0)}
>> BC<-function(WET,t) {ifelse(WET(t)>0, 0.0001, 0)}
>>
>> NP<-4
>> m1 <- matrix(0, NP,NP)
>> m2 <- matrix(0,NP,NP)
>> m3 <- matrix(0,NP,NP)
>>
>>
>> for (i in 1:NP)
>> {
>> for (j in 1:NP)
>> {
>> if ((i%%sqrt(NP)) == 0 & i!=j)
>> {
>> if(j == i+sqrt(NP) | j == i-1 | j == i-sqrt(NP))
>> {
>> m1[j,i] <- AB
>> m1[i,j] <- AB
>>
>>
>> m2[j,i] <- 0.00025
>> m2[i,j] <- 0.00025
>>
>> m3[j,i] <- BC
>>
>> m3[i,j] <- BC
>>
>> }
>> }
>> if (i%%sqrt(NP) == 1)
>> {
>> if(j == i+sqrt(NP) | j == i+1 | j == i-sqrt(NP) )
>> {
>> m1[j,i] <- AB
>>
>> m1[i,j] <- AB
>>
>>
>> m2[j,i] <- 0.00025
>> m2[i,j] <- 0.00025
>>
>> m3[j,i] <- BC
>>
>> m3[i,j] <- BC
>> }
>> }
>>
>> if (i%%sqrt(NP)!=0 & i%%sqrt(NP)!=1 & i!=j)
>> {
>> if(j == i+sqrt(NP) | j == i+1 | j == i-sqrt(NP) | j == i-1)
>> {
>> m1[j,i] <- AB
>>
>> m1[i,j] <- AB
>>
>> m2[j,i] <- 0.00025
>> m2[i,j] <- 0.00025
>>
>> m3[j,i] <- BC
>>
>> m3[i,j] <- BC
>> }
>> }
>> }
>> }
>>
>> Please could somebody advise me as to where I'm going wrong and how to
>> get it right? I have tried several different permutations and can't
>> seem to do so. I tried googling keywords "inserting function as matrix
>> element" but couldn't find any advice online. I'm very inexperienced
>> at coding so apologies if this is very simple.
>>
>> Thank you for any assistance you are able to give,
>> Aimee.
>>
>> ______________________________________________
>> 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.
>
> ______________________________________________
> 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.
--
Jim Holtman
Data Munger Guru
What is the problem that you are trying to solve?
Tell me what you want to do, not how you want to do it.
______________________________________________
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and provide commented, minimal, self-contained, reproducible code.
