程序1

op<-par(mfrow=c(4,2),mar=c(2,4,4,2))
n <- 200
for(i in 1:4) {
x <- NULL
while(is.null(x)) {
model<-list(ar=rnorm(1))
try(x<-arima.sim(model,n))
}
acf(x, main=paste( "ARMA(1,0)", "AR:", round(model$ar,digits=1) ))
points(0:50, ARMAacf(ar=model$ar,lag.max=50), col='red')
pacf(x,main="")
points(1:50,
ARMAacf(ar=model$ar,lag.max=50,pacf=T),
col='red')
}
par(op)