Em 02-09-2012 00:10, Jeff Newmiller escreveu:
I disagree that this answer is "wrong". If you want a mathematically correct
answer you are going to have to obtain it by applying intelligence to the algorithm in
which this calculation occurred.
Logarithms are the product of intelligence.
And the standard trick to make this sort of computation.
x <- 1e3
exp(x + log(0)) # zero
x <- 1e300
exp(x + log(0)) # zero
Rui Barradas
This is not a mailing list about numerical methods in general, so it probably
isn't appropriate to pursue that conversation here.
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CHEL HEE LEE <[email protected]> wrote:
I have some trouble to deal the value of 'NaN'. For example,
exp(1e3)
[1] Inf
exp(1e3)*0
[1] NaN
The correct answer should be 0 rather than NaN. I will very appreciate
if anyone can share some technique to get a correct answer.
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______________________________________________
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
______________________________________________
[email protected] mailing list
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
