control.matlab.ss

control.matlab.ss(A, B, C, D[, dt])

Create a state space system.

The function accepts either 1, 4 or 5 parameters:

ss(sys)

Convert a linear system into space system form. Always creates a new system, even if sys is already a StateSpace object.

ss(A, B, C, D)

Create a state space system from the matrices of its state and output equations:

\dot x = A \cdot x + B \cdot u y = C \cdot x + D \cdot u

ss(A, B, C, D, dt)

Create a discrete-time state space system from the matrices of its state and output equations:

x[k+1] = A \cdot x[k] + B \cdot u[k] y[k] = C \cdot x[k] + D \cdot u[ki]

The matrices can be given as array like data types or strings. Everything that the constructor of numpy.matrix accepts is permissible here too.

Parameters

  • sys (StateSpace or TransferFunction) – A linear system

  • A (array_like or string) – System matrix

  • B (array_like or string) – Control matrix

  • C (array_like or string) – Output matrix

  • D (array_like or string) – Feed forward matrix

  • dt (If present, specifies the sampling period and a discrete time) – system is created

Returns

out – The new linear system

Return type

StateSpace

Raises

ValueError – if matrix sizes are not self-consistent

See also

StateSpace, tf, ss2tf, tf2ss

Examples

>>> # Create a StateSpace object from four "matrices".
>>> sys1 = ss("1. -2; 3. -4", "5.; 7", "6. 8", "9.")

>>> # Convert a TransferFunction to a StateSpace object.
>>> sys_tf = tf([2.], [1., 3])
>>> sys2 = ss(sys_tf)