Hi [EMAIL PROTECTED] napsal dne 20.11.2008 16:15:44:
> > I tried to do some cycles using the ?for? function, but then I had to make > multiple ?for?s and it didn?t work. One of the major problems is that I > don?t know how to use the summation function on R. I did not find function summation. From your description I think you could look to cumsum or maybe sum or maybe to some other functions like rowSums. But if you want some more elaborated help first you shall provide some insight how your data look like. Try to make a simple example with fake data which everybody can reproduce. Regards Petr > > Best regards, > > P.Branco > > stephen sefick wrote: > > > > What have you tried so far? > > > > On Thu, Nov 20, 2008 at 7:40 AM, P.Branco <[EMAIL PROTECTED]> wrote: > >> > >> Dear all, > >> > >> I was wondering if you could help me with the following. > >> > >> I want to do calculate this equation: > >> > >> Ps(t)= (\xAD\xF4_(r=1)^N Xtr* 1/?drs)/(\xAD\xF4_(r=1)^N 1/?drs) > >> > >> Ps(t) ? Probability that taxon t will occur at site s (300 sites s) > >> N ? Number of sites = from 1 to 49 > >> Xtr ? Value for taxon t at site r (I have this information in a table, 40 > >> taxa (columns) t, 49 sites r) > >> drs ? Distance from site r to site s (this information is on a table, s > >> sites (columns)) > >> > >> I thought that R would be the software to use, but I am experiencing some > >> difficulties > >> > >> Thanks to everyone, > >> P.Branco > >> > >> -- > >> View this message in context: > >> http://www.nabble.com/Calculate-an-equation-tp20600332p20600332.html > >> Sent from the R help mailing list archive at Nabble.com. > >> > >> ______________________________________________ > >> 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. > >> > > > > > > > > -- > > Stephen Sefick > > Research Scientist > > Southeastern Natural Sciences Academy > > > > Let's not spend our time and resources thinking about things that are > > so little or so large that all they really do for us is puff us up and > > make us feel like gods. We are mammals, and have not exhausted the > > annoying little problems of being mammals. > > > > -K. Mullis > > ______________________________________________ > > 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. > > > > > > -- > View this message in context: http://www.nabble.com/Calculate-an-equation- > tp20600332p20603107.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > 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.
______________________________________________ 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.
