fx <- function(x) 2*exp(-2*x) Fx <- function(x) 1-exp(-2*x) iFx <- function(y) -log(1-y)/2 plot(Fx, 0, 3) iFx(0.1) iFx(0.3) iFx(0.5) iFx(0.7) u <- runif(1000) hist(u) x <- iFx(u) hist(x, col="blue") hist(x, col="blue", brea=seq(0,4,.25)) ### adicionar curva da densidade hist(x, col="gray", brea=seq(0,4,.25), freq=FALSE) plot(fx, 0, 4, add=TRUE, col=2) #### outra função fx2 <- function(x) ifelse(x>=1/3 & x<=1, 1/(2*x^2), 0) plot(fx2, 0, 1) integrate(fx2, 1/3, 1) ### usando o metodo da rejeição fx2(1/3) fx2(0.9)/4.5 args(runif) v <- runif(1000, 1/3, 1) hist(v, breaks=seq(1/3, 1, leng=10)) p <- fx2(v)/4.5 u2 <- runif(1000) x2 <- ifelse(u2