Plot multiple histograms in R with prob=TRUE

Question

I want to plot multiple histograms in R which do not show frequency, but the density instead:

A <- rnorm(100)
B <- rnorm(100)
hist1 <- hist(A,prob=TRUE,breaks=30)
hist2 <- hist(B,prob=TRUE,breaks=30) 
plot(hist1, col="red",lty=0, xlim=c(-4,4))
plot(hist2, col="blue", lty=0, xlim=c(-4,4), add=TRUE, main="Example")
lines(density(A))

However, my 'prob=TRUE' option apparently doesn't go through when plotting the objects. Can someone explain to me what I am doing wrong?

Answer 1

leave the prob=T out of the hist() command

hist1 <- hist(A,breaks=30)
hist2 <- hist(B,freq=F,breaks=30) 

And put freq=F into the plot command.

plot(hist1, col="red",lty=0, xlim=c(-4,4),freq=F)
plot(hist2, col="blue", lty=0, xlim=c(-4,4), add=TRUE, main="Example",freq=F)