[R] error with seq() used in for loop

[Berend Hasselman]

> On 11 Oct 2015, at 13:52, Maram SAlem <marammagdysalem at gmail.com> wrote:
> 
> Dear All,
> I have a question concerning the seq() function arguments when used in a
> for() loop.
> I'll simplify this question to make it more clear. Suppose I have a
> (5*3)matrix s (for ex.) and I need to write a function with  for() loop, in
> each step of the loop I need to generate a sequence whose upper limit is
> the ith element of the first row of s, then put the resulting sequences in
> a list. I used the following simple code (I've only included the first part
> of the function)
> 
> 
>> s<-matrix(c(1,0,1,0,1,1,0,0,1,0,0,0,0,0,1),nrow=5,byrow=TRUE)
>> simpfun<- function (x,n,m,p,alpha,beta)
> + {
> + LD<-list()
> + for (i in 1:m-1)
> + {
> + LD[[i]]<-seq(0,x[i],1)
> + }
> + print(LD)
> + }
>> mk<-simpfun(s[1,],n=6,m=4,p=0.3)
> Error in seq.default(0, x[i], 1) : 'to' must be of length 1
> 
> Although x is supposed to be the vector
> 1 0 1
> and thus x[1]=1, x[2]=0,x[3]=1.
> So I don't get why the error "Error in seq.default(0, x[i], 1) : 'to' must
> be of length 1" occurs in the first place.


Use 

for (i in 1:(m-1))

in stead of what you put in the function.
Read the section “Generating regular sequences” in the "An Introduction to R“ manual.

Berend