Calculating numerator and denominator polynomials of a transfer function

1. How do you find the numerator and denominator of a transfer function?
2. Are the roots of the denominator of a transfer function?
3. How do you find the numerator and denominator in Matlab?

How do you find the numerator and denominator of a transfer function?

[ num , den ] = tfdata( sys ) returns the numerator and denominator coefficients of the transfer function for the tf (Control System Toolbox), ss (Control System Toolbox) and zpk (Control System Toolbox) model objects or the array of model objects represented by sys .

Are the roots of the denominator of a transfer function?

The roots of the denominator polynomial are called the poles of the transfer function and the roots of the polynomial in the numerator are zeros.

How do you find the numerator and denominator in Matlab?

To extract the numerator and denominator of a rational symbolic expression, use the numden function. The first output argument of numden is a numerator, the second output argument is a denominator. Use numden to find numerators and denominators of symbolic rational numbers.