Dear all,
I have discovered a bug in the standard rep() function: At certain
values, rep() does not replicate the element by the proper number of times:
> a <- (1-0.9)*100
> a
[1] 10
> length(rep(1,times=a))
[1] 9
> length(rep(1,each=a))
[1] 9
As shown, this happens as well for the times= as for the each=
parameter. It does not depend on the kind of element that is to be repeated:
> length(rep("abc",each=a))
[1] 9
I tried to narrow down the bug, but haven't really managed to find a
pattern behind the bug. Here is a list with values for a (see above)
that returns a false object ( after the value for a, i've collected the
expected length and the length that is produced by r):
# mistake at
(1-0.9)*100 10 9
(1-0.8)*100 20 19
(1-0.8)*1000 200 199
(1-0.9)*1000 100 99
(1-0.9)*10 1 0
(1-0.8)*10 2 1
(1-0.9)*1000000000 100000000 99999999
(2-1-0.9)*100 10 9
(10/10-0.9)*100 10 9
# the following sets for a work fine
(1+0.1)*100
(1-0.1)*100
(1-0.7)*100
(1-0.99)*1000
(1-0.7)*10
(1-0.90)*10
(1-0.95)*100
(1-0.95)*1000
(2-0.9)*1000
(2-1.9)*100
(1.1-1)*100
(10-9)*100
Did I make any mistake? Or where else should I address this problem?
Thanks and best regards,
Samuel
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