under "Value", ?dbinom says
If ?size? is not an integer, ?NaN? is returned.
That should be something like
If ?size? is not an integer, ?NaN? is returned (or 'NA' for
rbinom).
... at least that's what happens for me under svn rev 70138, Ubuntu 14
> rbinom(1,size=0.5,prob=0.5)
[1] NA
Warning message:
In rbinom(1, size = 0.5, prob = 0.5) : NAs produced
> dbinom(1,size=0.5,prob=0.5)
[1] NaN
Warning message:
In dbinom(1, size = 0.5, prob = 0.5) : NaNs produced