[R] Optimization problem

Rui Barradas ruipbarradas at sapo.pt
Thu Apr 11 12:04:06 CEST 2013


You cannot change the numerical accuracy, it's a built-in constant. To 
see it use

.Machine$double.eps  # smallest value different from zero

Actually, .Machine$double.eps is the "the smallest positive 
floating-point number x such that 1 + x != 1"

You can try the following function

is.zero <- function(x, eps = .Machine$double.eps^0.5) abs(x) < eps

is.zero(your_value)  # TRUE?

Or even try ?all.equal

all.equal(your_value, 0)

Hope this helps,

Rui Barradas

Em 10-04-2013 22:13, nntx escreveu:
> Rui, thanks for your reply. You meant that it is the issue of accuracy? So if
> I change the numerical accuracy, my results can be output? Thanks a lot!
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