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Subject: Re: exp function
Date: Mon, 20 Jun 2011 20:44:05 +0000 (UTC)
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Hello Matt,

The problem is still there  as now value of (log(N) - 921)  is very less again so exponent of this gives zero o/p. :(

"Matt J" wrote in message <ito8eu$ge4$1@newscl01ah.mathworks.com>...
> "Nilesh Goel" wrote in message <ito85l$fgm$1@newscl01ah.mathworks.com>...
> > i s there a limit of exp(x) for which it will only give zero as answer.
> > 
> > In one of my equation exp(-921) is multiplied by a large constant but the answer is zero. I observe exp(-921) returns zero so even multiply it with large no. will return zero.
> > 
> > Is this a limitation of Matlab or there is any alternative to get the small values also.
> 
> 
> Instead of implementing as N*exp(-921), perhaps implement as
> 
> exp( log(N)-921 )