Why is "Diagnostic Information" displayed when i run an AR/ARIMA model?

Hi, I've written a function that fits an AR(8) model to a univariate time series. The function works fine, but when I run it, it displays Diagnostic Information, information about the different iterations and a summary of the parameters.

I tried mixing with the optimset command, but I can't figure out how I turn these outputs off. Does anyone have andy ideas?

Regards, Karl