You get 0 because you did not specify lower and upper bounds that define the hyper-rectangle; therefore, the default is used which is (0,1)^4.
Specify the proper lower and upper bounds. Ravi. ____________________________________________________________________ Ravi Varadhan, Ph.D. Assistant Professor, Division of Geriatric Medicine and Gerontology School of Medicine Johns Hopkins University Ph. (410) 502-2619 email: rvarad...@jhmi.edu ----- Original Message ----- From: Dmlong21 <dml...@bios.unc.edu> Date: Tuesday, March 29, 2011 3:11 pm Subject: Re: [R] Integration with variable bounds To: r-help@r-project.org > Thanks for the tip but all I get is 0 for the integral. Any other > suggestions? > > int <- function(y){ > u2 = y[1] > z2 = y[2] > u1 =y[3] > z1 = y[4] > > reg.nonzero <- (u2 > z1 & u2 < z2) & (z2 > z1 & z2 < 12) & (u1 > 4 & > u1 < > z1) & (z1 > 4 & z1 < 12) > > > ff <- ifelse (reg.nonzero, u1*(z1-u1)*u2*(z2-u2)*exp(-0.027*(12-z2)), > 0) > > > return(ff) > > > } > > > cuhre(4,1,int) > > -- > View this message in context: > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help@r-project.org mailing list > > PLEASE do read the posting guide > 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.