Avoiding in underflow in double -> real conversions

List-

I've got a calculation that, due to its use of exp(), is produces double
precision intermediate results which I ultimately need to cast back to real
to store in a table column. However, with certain inputs, this results in an
underflow error. Is there any way outside of an exception-trapping plpgsql
function to performance the conversion and simply cause underflows to result
in a 0?

Thanks for any ideas.

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- David T. Wilson
david(dot)t(dot)wilson(at)gmail(dot)com