[R] hist single block plot issue

[ap]

# CASE 1
# The following plots a single cell or block for all three location 0,1,2.
y <- rep(2,8)
hist(y)                # why is this a single block?
hist(y,xlim=c(0,2))    # same thing
hist(y,breaks=2)       # same

# CASE 2
# adding a different value, plots as expected
y <- append(y,0)
hist(y)                # plots as expected


In most cases of the data I have variances in the data so this is not an
issue. In some situations case #1 appears and I would like to 
differentiate it among the other values.

Thanks