enty-wise closest element

Thank you very much for your quick answers.

Sorry, but i forgot to explain i want to find the closest and smaller element 
for each entry, so ind1[3] is smaller as 11 and close to 11, ind1[2] is 
smaller as 5 and close to 5 and ind1[1] is smaller than 3 and close to 3.

ind2[ 1 + findInterval(ind1,ind2) ]

best regards

Andreas

 On Jan 17, 2010, at 11:00 AM, Andreas Wittmann wrote:

 Dear R-users,

 i have a simple problem maybe, but i don't see the solution. i want to 
 find the entry-wise closest element of an vector compared with another.

 ind1<-c(1,4,10)
 ind2<-c(3,5,11)

 for (i in length(ind2):1)
 {
 print(which.min(abs(ind1-ind2[i])))
}

 for ind2[3] it should be ind1[3] 10, for ind2[2] it should be ind1[2] 4 
 and for ind2[1] it should be ind1[1] 1. but with the for-loop above i 
 get ind1[3], ind1[2] and ind1[2].

 any suggestions are quite welcome.

 You are failing to use the indices that which.min is providing. (And I
 think the closest in ind1 to ind2[1] is not 1, but rather 4, so see if
 this looks more responsive to your expectations:

 for (i in length(ind2):1)

 + {
 + print( ind1[which.min(abs(ind1-ind2[i]))] )
 + }
 [1] 10
 [1] 4
 [1] 4

 best regards

 Andreas

 David Winsemius, MD
 Heritage Laboratories
 West Hartford, CT