select (Control Design and Simulation Module, MathScript Function)

Member of the reduce class.

Syntax

SysSel = select(SysIn, i, j, k)

SysSel = select(SysIn, i, j, k, ord)

Constructs a new system model by selecting inputs and/or outputs from an existing model. You also can select states from a state-space model.

Name	Description
SysIn	Specifies a linear time-invariant (LTI) model in transfer function, zero-pole-gain, or state-space form.
i	Specifies a list of model inputs to keep from the SysIn model. The default value is empty. A value of –1 specifies that you want to keep all inputs. i is a real vector.
j	Specifies a list of model outputs to keep from the SysIn model. The default value is empty. A value of –1 specifies that you want to keep all outputs. j is a real vector.
k	Specifies a list of model states to keep from the SysIn model. The default value is empty. A value of –1 specifies that you want to keep all states. This input is valid only if you specify a state-space model. k is a real vector.
ord	Specifies whether the SysSel model orders the selected inputs/outputs/states in the order in which you selected them. To enable this behavior, specify a value of 1 for this input. If you specify a value of 0, the SysSel contains the selected inputs/outputs/states in the order in which they existed in the SysIn model. The default value is 0.

Name	Description
SysSel	Returns the SysIn model with only the specified inputs and outputs. If you specified a state-space model for the SysIn input, the SysSel model also contains the specified states.

SysIn = tf(1, 2, 3, 4, 5, 6, -1, -2, -3, -4, -5, -6, [2 3]);SysSel= select(SysIn, [2 1], [2 1], 1);