#This generates exponentials from uniforms#
nsim<-10000;u<-runif(nsim);
y<--log(u);
hist(y,main="Exponential",freq=F,col="green",breaks=50)
par(new=T)
plot(function(x)dexp(x), 0,10,xlab="",ylab="",xaxt="n",yaxt="n")