Oliver Kullmann <O.Kullmann <at> swansea.ac.uk> writes: > > Thanks for the information.
What I meant were formulas like \int 1/\log(t)^2 dt = -t/\log(t) + li(t) \int 1/\log(t)^3 dt = 1/2 * ( -t/\log(t)^2 - t/\log(t) + li(t) ) and higher forms that can be expressed through the Gamma function. I am certain I 've seen them in AandS' handbook (where else?), but sure cannot remember in which chapter or page. Which logarithmic integrals do you really need, and on what range? Regards, Hans Werner > On Sat, May 29, 2010 at 01:15:29PM +0000, Hans W. Borchers wrote: > > Oliver Kullmann <O.Kullmann <at> swansea.ac.uk> writes: > > > > > > > > Hello, > > > > > > I couldn't find information on whether the logarithmic integrals > > > > > > Li_m(x) = integral_0^x log(t)^(-m) dt > > > > > > for x >= 0 are available in R? > > [...] > > I found gsl at http://cran.r-project.org/web/packages/gsl/index.html. > > > and elliptic integrals are part of the 'gsl' package, so > > > > library('gsl') > > x <- seq(2, 10, by=0.5) > > y <- expint_Ei(log(x)) > > y > > > > See e.g. the Handbook of Mathematical Functions for how to reduce higher > > logarithmic integrals. > > However here I wasn't succesful: Going through the chapter > > http://www.math.ucla.edu/~cbm/aands/page_228.htm > > I didn't find any mentioning of the higher logarithmic integrals. > [...] > > Also a google search on "higher logarithmic integrals", "logarithmic > integrals" > or "li_n(x)" doesn't reveal anything, so I would be thankful for a hint. > > Thanks again! > > Oliver > ______________________________________________ R-help@r-project.org 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.