Probability <- function(N, f, w, b, y, t, q) { #N is the number of lymph nodes #f is the fraction of Dendritic cells (in the correct node) that have the antigen #w is time in terms of hours #b is the starting position (somewhere in the node or somewhere in the gap between nodes. It is a number between 1 and (x+t)) #y is the number of time steps it takes to traverse the gap (8hr/y) #t is the number of time steps it takes to traverse a node. (24hours total -- so 24hr/t) #q is the length of the time step m <- ceiling(w/q) A <- 1/N B <- 1-A C <- 1-f D <- (((m+b-1)%%(y+t))+1)
if (b<=t) {########starts inside node if (m<=(t-b)){return(B + A*(C^m))} # start & end in first node if (D<=t) { # we finish in a node a <- (B + A*(C^(t-b))) #first node b <- ((B + A*(C^t))^(floor((m+b)/(y+t))-1)) # intermediate nodes (if any) c <- (B + A*(C^D)) # last node return(a*b*c) } else {return(Probability(N, f, ((m*q)-q), b, y, t, q))} ## finish in a gap } else {###### starts outside node if (m<=(y+t-b)) {return(1)} #also end in the gap if (D<=t) { #end in a node b <- ((B + A*(C^t))^(floor((m/(y+t))))) c <- (B + (A*(C^D))) return(b*c) } else {return(Probability(N, f, ((m*q)-q), b, y, t, q))} #outside node } } This works for most values of 'w' (time): > Probability(100, 0.001, 1, 1, 20, 20, (10/60)) [1] 0.9999401 > Probability(100, 0.001, 2, 1, 20, 20, (10/60)) [1] 0.9998807 > Probability(100, 0.001, 3, 1, 20, 20, (10/60)) [1] 0.9998215 > Probability(100, 0.001, 4, 1, 20, 20, (10/60)) Error: evaluation nested too deeply: infinite recursion / options(expressions=)? But once I get to w=4 I get an infinite recursion. I get that there is a recursion in my function but I'm not sure why it wouldn't work. After a certain point (D<=t) would be true. Any help, please? -- View this message in context: http://r.789695.n4.nabble.com/An-infinite-recursion-error-please-explain-tp3688260p3688260.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.