Hello
On 30 Aug 2007, at 16:08, willem vervoort wrote: > > What happens when you raise a negative value to a power and the result > is a very large number? > [snip] > I loaded package Brobdingnag and tried: > as.brob(x^B) > [1] NAexp(NaN) NAexp(NaN) NAexp(NaN) NAexp(NaN) NAexp(NaN) >> as.brob(x)^B > [1] NAexp(187.67) NAexp(187.65) NAexp(187.63) NAexp(187.61) > > I guess I must be misunderstanding something fundamental. > As others have said, in this case one needs complex arithmetic. In a Brobdingnagian context one would use Glubbdubdribian numbers: > x <- seq(-51,-49,length=10) > as.glub(x)^112313.3 [1] -exp(441600)-exp(441600)i -exp(441110)-exp(441110)i -exp (440610)-exp(440610)i [4] -exp(440120)-exp(440120)i -exp(439620)-exp(439620)i -exp (439120)-exp(439120)i [7] -exp(438620)-exp(438620)i -exp(438120)-exp(438120)i -exp (437610)-exp(437610)i [10] -exp(437100)-exp(437100)i > -- Robin Hankin Uncertainty Analyst National Oceanography Centre, Southampton European Way, Southampton SO14 3ZH, UK tel 023-8059-7743 ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
