Hi, Thanks a lot for answer. It is what I mean. But the code does not seem to work (
Le Jul 19, 2012 à 8:52 AM, Petr Savicky [via R] a écrit : > On Wed, Jul 18, 2012 at 06:02:27PM -0700, bilelsan wrote: > > Leave the Taylor expansion aside, how is it possible to compute with [R]: > > f(e) = e1 + e2 #for r = 1 > > + 1/2!*e1^2 + 1/2!*e2^2 + 1/2!*e1*e2 #for r = 2, excluding e2*e1 > > + 1/3!*e1^3 + 1/3!*e1^2*e2 + 1/3!*e2^2*e1 + 1/3!*e2^3 #for r = 3, excluding > > e2*e1^2 and e1*e2^2 > > + ... #for r = k > > In other words, I am trying to figure out how to compute all the possible > > combinations as exposed above. > > Hi. > > For a general r, do you mean the following sum of products? > > 1/r! (e1^r + e1^(r-1) e2 + ... e1 e2^(r-1) + e2^r) > > If this is correct, then try > > f <- 0 > for (r in 1:k) { > f <- f + 1/factorial(r) * sum(e1^(r:0)*e2^(0:r)) > } > > Hope this helps. > > Petr Savicky. > > ______________________________________________ > [hidden email] 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. > > > If you reply to this email, your message will be added to the discussion > below: > http://r.789695.n4.nabble.com/Re-taylor-expansions-with-real-vectors-tp4636948p4636989.html > To unsubscribe from Re: taylor expansions with real vectors, click here. > NAML -- View this message in context: http://r.789695.n4.nabble.com/Re-taylor-expansions-with-real-vectors-tp4636948p4637388.html Sent from the R help mailing list archive at Nabble.com. [[alternative HTML version deleted]]
______________________________________________ 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.