Hi All!

Please find code and the respective lists below.  My problem: I specify the
case that lilwin[[p]] is not an NA and want the code found in iwish to be
returned ONLY for that case.  Why do I get a list of length 2 (and why is
NULL the first element)? I understand that the code below is quite
senseless.  I have run into a problem while working on a large project and
wanted to simplify it in order for it to be more understandable and
accessible.  If I should not be using the if function, please let me know
what I should be doing instead.  I know that I must use the for function for
my project.  The thing I most want to understand is how, after specifying a
certain condition, one may save certain data that occurs when that condition
is met.   I hope I have been clear enough!

Thank you very much for your help!
Anna

biglist<-list(a=1:4,b=2:6)
lilwin<-list(x=NA,y=2)
lilloss<-list(m=1,n=3)



> biglist$a
[1] 1 2 3 4

$b
[1] 2 3 4 5 6
> lilwin$x
[1] NA

$y
[1] 2
> lilloss$m
[1] 1

$n
[1] 3


iwish<-list()
for(p in 1:length(biglist)){
if(is.na(lilwin[[p]])==F) iwish[p]<-list(biglist[[p]][lilwin[[p]]])
}


> iwish[[1]]
NULL

[[2]]
[1] 3

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