Thanks Jim. But a narrower problem still remains. Please, look at this new code:
lambda=c(.6,.3) integral = function(u) { theta = (atan(.6*u) + atan(.3*u))/2 - .1*u/2 rho = (1+.6^2*u^2)^(1/4) * (1+.3^2*u^2)^(1/4) integrand = sin(theta)/(u*rho) } > integrate(integral,0,Inf)$value [1] 1.222688 If I replace theta = sum(atan(lambda*u))/2 - .1*u/2 I get > integrate(integral,0,Inf)$value [1] 1.517134 It seems there is a problem between the sum() and integrate() functions. Is there a way to solve this problem? Thanks in advance. Rogerio. ---------- Part of the Original Message ----------- > They do give the same answer, unfortunately the examples you sent were not > the same. Integral2 was missing a 'sin'. So I would assume there might be > something else wrong with your functions. You might want to try breaking it > down into smaller steps so you can see what you are doing. It definitely is > hard to read in both cases. > > Jim Holtman > Cincinnati, OH > +1 513 646 9390 > > What is the problem you are trying to solve? ______________________________________________ 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.