[R] test multiple objects for being equal length

[Liaw, Andy]

Wrapping the suggestions into a function:

> sameLength <- function(...) {
+     n <- sapply(list(...), length)
+     all(n == n[1])
+ }
> sameLength(double(1), double(2))
[1] FALSE
> sameLength(double(1), double(1), list(x=1))
[1] TRUE

[Note that if you have lots of objects to compare, length(unique(...))==1
will not be as efficient.]

HTH,
Andy


> From: Manuel Gutierrez
> 
> I could not find any help pages on How to test many
> objects for being of equal length
> Something like identical for more than two objects?
> x<-1:6
> y<-1:10
> z<-3:5
> ## For two objects I can do:
> identical(length(x),length(y))
> ## For more than two I currently can do:
> length(unique(c(length(x),length(y),length(z))))==1
> 
> but there must be a better way.
> Thanks,
> M
> 
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