[R] Drawing a reference line for a qqplot with reference to Weibull distribution

[Benjamin Dickgiesser]

Hi,
I'm trying to create a qqplot with reference to a Weibull distribution
including a reference line. This is my current code:

lights.data <- scan("lights.dat")
#Generate Weibull quantiles
prob.grid <- ppoints(length(lights.data))
prob.quant <- qweibull(prob.grid , 1.5,4)
#Draw QQ plot
qqplot(prob.quant,lights.data)
#add red reference line
qqline(lights.data,col = 2)

Obviously the reference line isn't correct this way. How would I go
about fitting one?

I am grateful for any help,
Ben