How to realize Poles and zeros at infinity??especially through transfer function?

1. How do you find the poles and zeros of a transfer function in Matlab?
2. How do you determine stability from poles and zeros?

How do you find the poles and zeros of a transfer function in Matlab?

First convert the poles and zeros to transfer function form, then call fvtool . Click the Pole/Zero Plot toolbar button, select Analysis > Pole/Zero Plot from the menu, or type the following code to see the plot. To use zplane for a system in transfer function form, supply row vector arguments.

How do you determine stability from poles and zeros?

If all the poles lie in the left half of the s-plane, then the system is stable. If the system has two or more poles in the same location on the imaginary axis, then the system is unstable. If the system has one or more non-repeated poles on the imaginary axis, then the system is marginally stable.