bounds property

'bound' is a list of strictly increasing boundaries between buckets.

Note that a list of length N-1 defines N buckets because of fenceposting. See comments on bucket_options for details. The i'th finite bucket covers the interval [bound[i-1], bound[i]) where i ranges from 1 to bound_size() - 1. Note that there are no finite buckets at all if 'bound' only contains a single element; in that special case the single bound defines the boundary between the underflow and overflow buckets. bucket number lower bound upper bound i == 0 (underflow) -inf bound[i] 0 < i < bound_size() bound[i-1] bound[i] i == bound_size() (overflow) bound[i-1] +inf