[ADMB Users] very small number math

[Fowler, Mark]

Hello,

I think I've hit a precision limit, looking for a solution along the
same sort of lines as posfun or mfexp. My program stops (no error
message) in a loop when a particular equation attempts to divide 19616.8
by 7.57411e-154. The preceding iteration worked with 21666/5.73085e-132.
These are silly starting estimates of a value which will get reasonable
with a little fitting, I just want to accept a maximal result instead of
bombing. In this case I can just use a min function on the denominator,
but wonder if there isn't a conventional approach for this situation,
say defining a minimum number threshold.

		Mark Fowler
		Population Ecology Division
		Bedford Inst of Oceanography
		Dept Fisheries & Oceans
		Dartmouth NS Canada
		B2Y 4A2
		Tel. (902) 426-3529
		Fax (902) 426-9710
		Email Mark.Fowler at dfo-mpo.gc.ca
		Home Tel. (902) 461-0708
		Home Email mark.fowler at ns.sympatico.ca


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