limits of float8

Dear all,

What are the limits of float8?

The user guide says variable-precision, 14 decimal places range but I'm not
sure how that translates to a minimum value.

I'm asking because I'm storing probability scores (range 0 to 1) with some
scores very small indeed.

The very small scores are all entered in scientific notation.

From experimentation, the smallest value I seem to be able to enter is
around 2.225e-308.  Is this 'correct'?

This is PG 6.4 compiled with cc under Irix 5.3.

Cheers,

Stuart.
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| Stuart Rison            | Ludwig Institute for Cancer Research |
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