control.tf2ss

control.tf2ss(*args)

Transform a transfer function to a state space system.

The function accepts either 1 or 2 parameters:

tf2ss(sys)

Convert a linear system into transfer function form. Always creates a new system, even if sys is already a TransferFunction object.

tf2ss(num, den)

Create a transfer function system from its numerator and denominator polynomial coefficients.

For details see: tf()

Parameters:

sys: LTI (StateSpace or TransferFunction)

A linear system

num: array_like, or list of list of array_like

Polynomial coefficients of the numerator

den: array_like, or list of list of array_like

Polynomial coefficients of the denominator

Returns:

out: StateSpace

New linear system in state space form

Raises:

ValueError

if num and den have invalid or unequal dimensions, or if an invalid number of arguments is passed in

TypeError

if num or den are of incorrect type, or if sys is not a TransferFunction object

See also

ss, tf, ss2tf

Examples

>>> num = [[[1., 2.], [3., 4.]], [[5., 6.], [7., 8.]]]
>>> den = [[[9., 8., 7.], [6., 5., 4.]], [[3., 2., 1.], [-1., -2., -3.]]]
>>> sys1 = tf2ss(num, den)

>>> sys_tf = tf(num, den)
>>> sys2 = tf2ss(sys_tf)