Contents

initopspec

Initialize operating point specification values

Syntax

opnew=initopspec(opspec,oppoint)
opnew=initopspec(opspec,x,u)
opnew=initopspec(opspec,xstruct,u)

Alternatives

As an alternative to the initopspec function, initialize operating point specification values in the Linear Analysis Tool. See Import and Export Specifications For Operating Point Search.

Description

opnew=initopspec(opspec,oppoint) initializes the operating point specification object, opspec, with the values contained in the operating point object, oppoint. The function returns a new operating point specification object, opnew. Create opspec with the function operspec. Create oppoint with the function operpoint or findop.

opnew=initopspec(opspec,x,u) initializes the operating point specification object, opspec, with the values contained in the state vector, x, and the input vector, u. The function returns a new operating point specification object, opnew. Create opspec with the function operspec. You can use the function getxu to create x and u with the correct ordering.

opnew=initopspec(opspec,xstruct,u) initializes the operating point specification object, opspec, with the values contained in the state structure, xstruct, and the input vector, u. The function returns a new operating point specification object, opnew. Create opspec with the function operspec. You can use the function getstatestruct or getxu to create xstruct and the function getxu to create u with the correct ordering. Alternatively, you can save xstruct to the MATLAB® workspace after a simulation of the model. See the Simulink® documentation for more information on these structures.

Examples

Create an operating point using findop by simulating the magball model and extracting the operating point after 20 time units.

oppoint=findop('magball',20)

This syntax returns the following operating point:

 Operating Point for the Model magball.
 (Time-Varying Components Evaluated at time t=20)

States: 
----------
(1.) magball/Controller/PID Controller/Filter
      x: 2.33e-007    
(2.) magball/Controller/PID Controller/Integrator
      x: 14           
(3.) magball/Magnetic Ball Plant/Current
      x: 7            
(4.) magball/Magnetic Ball Plant/dhdt
      x: 3.6e-008     
(5.) magball/Magnetic Ball Plant/height
      x: 0.05         
 
Inputs: None 
----------

Use these operating point values as initial values in an operating point specification object.

opspec=operspec('magball');
newopspec=initopspec(opspec,oppoint)

The new operating point specification object is displayed.

 Operating Specification for the Model magball.
 (Time-Varying Components Evaluated at time t=0)

States: 
----------
(1.) magball/Controller/PID Controller/Filter
      spec:  dx = 0,  initial guess:     2.33e-007
(2.) magball/Controller/PID Controller/Integrator
      spec:  dx = 0,  initial guess:            14
(3.) magball/Magnetic Ball Plant/Current
      spec:  dx = 0,  initial guess:             7
(4.) magball/Magnetic Ball Plant/dhdt
      spec:  dx = 0,  initial guess:      3.6e-008
(5.) magball/Magnetic Ball Plant/height
      spec:  dx = 0,  initial guess:          0.05
 
Inputs: None 
----------
 
Outputs: None 
----------

You can now use this object to find operating points by optimization.

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