Error in xy.coords(x, y, xlabel, ylabel, log) : 'x' and 'y' lengths differ

Question

I am defining a function and trying to plot it for x > max{b1,b2} :

b1<-1
b2<-2
b<-1
l<-1
fn <- function(x,b1,b2,b,l){
         result <- b/x * ((1-(sqrt(1-(b1/x)^l)*sqrt(1-(b2/x)^l)))^(- 1/l))
         return(result)
          } 
fn1 <- fn(x,b1,b2,b,l)
x<-seq(3,20,0.1)
plot(x,fn1,type="l")

It's working for these values but when I am changing x as follows x<-seq(3,100,0.1), it's showing an error:

Error in xy.coords(x, y, xlabel, ylabel, log) : 'x' and 'y' lengths differ

Can you suggest what is the mistake here? How it can be removed?

Answer 1

Not sure what operation do you want after the b/x term, but It reads the [ ] as an index, try:

fn <- function(x,b1,b2,b,l){
  result <- b/x * (1-(sqrt(1-(b1/x)^l)*sqrt(1-(b2/x)^l)))**(- 1/l)
  return(result)
} 

Answer 2

the results line in your function has improper syntax. it should be as follows

result <- b/x*(1-(sqrt(1-(b1/x)^l)*sqrt(1-(b2/x)^l)))*(- 1/l)

Note the differences:

• no [ ] are used as they have a different meaning than ( ) in R.
• multiplications * have been fixed throughout