In this calculation: (dg0%*%t(dx0)) is [,1] [,2] [1,] 0 -0.75 [2,] 0 0.50
So: exp2 = NaN It is extremely easy to find out the issue if you go back line by line, this is a basic procedure of debugging. Please do it yourself next time. On Mon, Jan 13, 2014 at 3:09 PM, IZHAK shabsogh <ishaqb...@yahoo.com> wrote: > kindly help me fine what is the mistake with following: > my aim is to compute those steps and obtain a vector with values (3,5) > but i am geting (NAN,NAN) > > Q<-matrix(c(5,-3,-3,2),2,2) > b<-rbind(0,1) > H0<-diag(2) > x0<-rbind(0,0) > d0<-b > g0<--b > a0<--(t(g0)%*%d0)/(t(d0)%*%Q%*%d0) > x1<-x0+a0[,1]*d0 > dx0<-x1-x0 > g1<-Q%*%x1-b > dg0<-g1-g0 > exp1<-(t(dg0)%*%H0%*%dg0)/(t(dg0)%*%dx0) > exp2<-(dx0%*%t(dx0))/(dg0%*%t(dx0)) > exp3<-(dx0%*%t(dg0)%*%H0 +H0%*%dg0%*%t(dx0))/(dx0%*%t(dg0)) > H1<-H0+(1+exp1[,1])*exp2-exp3 > d1<--H1%*%g1 > a2<-(t(g1)%*%d1)/(t(d1)%*%Q%*%d1) > x2<-x1+a2[,1]*d1 > > [[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. > > [[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.