*
* Example 1.4.6 from page 20
*
* This generates a series of 200 N(0,1) points. (%ran(sigma)) returns a
* N(0,sigma**2)).
*
set x 1 200 = %ran(1.0)
*
* This computes and graphs the autocorrelation function of the series, computing
* 40 lags.
*
@acf(number=40) x