John R Pierce <pierce@hogranch.com> writes:
> Tom Lane wrote:
>> You do realize that float4/real is only good to six decimal places
>> on most platforms?
> and importantly, are stored as binary fractions. 0.10000 decimal is a
> repeating fraction in binary, its like .1100110011.... x 2^-2 or
> something as a FLOAT.
Right, and conversely a fraction that's cut off at a certain number of
base-2 digits often corresponds to a repeating pattern of base-10
digits. I once had a clue about the exact laws for this, but it was
many years ago :-(
regards, tom lane