You're kidding, right?! See ?traceback for browsing the call stack after an error.
Also ?browser, ?debug, and ?recover for other debugging options. -- Bert On Mon, Feb 18, 2013 at 1:28 PM, Aya Anas <aa...@feps.edu.eg> wrote: > Dear all, > > I tried running the following syntax but it keeps running for about 4 hours > and then i got the following errors: > > Error in if (is.na(f0$objective)) { : argument is of length zero > In addition: Warning message: > In is.na(f0$objective) : > is.na() applied to non-(list or vector) of type 'NULL' > > Here is the syntax itself: > > library('nloptr') > library('pracma') > # objective function > f <- function(x,s) {m<-100 > t<-2*m+1 > H<-matrix(data=NA,nrow=t,ncol=t) > I<-diag(t) > delta<-2*x[1]/t > z<--x[1]+.5*delta > range1<-t > for (i in 1:range1){ > z_i=-x[1]+(i-.5)*delta > for (j in 1:range1){ > up<-(((-x[1]+j*delta-(1-x[2])*z_i)/x[2]))-s > down<-(((-x[1]+(j-1)*delta-(1-x[2])*z_i)/x[2]))-s > H[i,j]<-pnorm(up,mean=0,sd=1)-pnorm(down,mean=0,sd=1)} > } > > K<-solve(I-H) > one <- matrix(1,nrow=t,ncol=1) > u <- matrix(0,nrow=m,ncol=1) > y<-c(u, 1, u) > z<-t(y) > ARLV<-K%*%one > ARLV2<-t(ARLV) > return((ARLV2%*%y)/3) > } > # constraint function > eval_g0 <- function(x) {m1<-100 > t1<-2*m1+1 > H1<-matrix(data=NA,nrow=t1,ncol=t1) > I1<-diag(t1) > delta1<-2*x[1]/t1 > z1<--x[1]+.5*delta1 > range11<-t1 > for (i1 in 1:range11){ > z_i1=-x[1]+(i1-.5)*delta1 > for (j1 in 1:range11){ > up1<-((-x[1]+j1*delta1-(1-x[2])*z_i1)/x[2]) > down1<-((-x[1]+(j1-1)*delta1-(1-x[2])*z_i1)/x[2]) > H1[i1,j1]<-pnorm(up1,mean=5,sd=1)-pnorm(down1,mean=5,sd=1)} > } > > K1<-solve(I1-H1) > one1 <- matrix(1,nrow=t1,ncol=1) > u1 <- matrix(0,nrow=m1,ncol=1) > y1<-c(u1, 1, u1) > z1<-t(y1) > ARLV1<-K1%*%one1 > ARLV21<-t(ARLV1) > > return( abs((ARLV21%*%y1)-500)-1) > } > eval_f0 <- function(x) romberg(function(s) f(x, s), 0, 6) > of <- nloptr( x0=c(0.653,0.09), > eval_f=eval_f0, > lb = c(0,0), > ub = c(6,1), > eval_g_ineq = eval_g0, > opts = list("algorithm"="NLOPT_LN_COBYLA", "maxeval"=1000), > ) > print(of) > > Regards, > Aya > > [[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. -- Bert Gunter Genentech Nonclinical Biostatistics Internal Contact Info: Phone: 467-7374 Website: http://pharmadevelopment.roche.com/index/pdb/pdb-functional-groups/pdb-biostatistics/pdb-ncb-home.htm ______________________________________________ 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.