I have a function that perfectly works, and I call it tempQ which is a function of X. I want to create a new function in which every value less than zero is zero. So I write:
Qpdf <- function(X) {
if ( tempQ(X) > 0 ) tempanswer <- tempQ(X)
else tempanswer <- 0
return(tempanswer)
}
This new Qpdf(X) works pretty well when I give some test numbers, but when I want to plot it, R gives me this error message:
> plot.function(Qpdf, from = 200 , to= 600)
Error in curve(expr = x, from = from, to = to, xlim = xlim, ylab = ylab, :
'expr' did not evaluate to an object of length 'n'
In addition: Warning message:
In if (tempQ(X) > 0) tempanswer <- tempQ(X) else tempanswer <- 0 :
the condition has length > 1 and only the first element will be used
Actually, I want this function because I want to integrate it and I do not need its negative values to be in the integral intervals, but it does not for the integral to and gives me the same error:
> integrate(Qpdf , 200 , 800)
Error in integrate(Qpdf, 200, 800) :
evaluation of function gave a result of wrong length
In addition: Warning message:
In if (tempQ(X) > 0) tempanswer <- tempQ(X) else tempanswer <- 0 :
the condition has length > 1 and only the first element will be used
How can I solve this problem?
