# Linear

Command ElementThe Linear class is a command element that controls the solver parameters for linear/eigen mode analysis.

Linear

## Attribute Summary

Name Property Modifiable by command? Designable?
id Int() Yes No
label Str()
animation_scale Double()
oml Bool ()
matlab Bool ()
eigensol Bool ()
pinput Reference (Pinput)
poutput Reference (Poutput)
statemat Bool ()
nodamping Bool ()
kinetic Bool ()
cutoff_frequency Double (-1)
pstate Reference (Pstate)

## Usage

#1: define a linear command to generate OML state space representation of the model
Linear(simulink_mdl = False, oml = True, matlab = False, statemat =True)

#2: Define a Plant State entity and reference that in the Linear command
Linear(simulink_mdl = False, oml = True, matlab = False, statemat =True, pstate=Pstate(variables=[var1, var2]))

#3: Define Plant Input and Plant Output Linear command
Linear(statemat =True, pinput=Pinput(variables = [var1]), poutput=Poutput(variables = [var2]))

## Attributes

animation_scale
Double
Specifies a factor for magnifying the mode shapes during animation.
This attribute is optional. MotionSolve automatically sets animation_scale to 1.0 when it is not specified.
Bool
Specifies whether the A, B, C, and D matrices that are calculated are to be written out in Simulink MDL format or not. Select from True and False.
The default is simulink_mdl = False.
oml
Bool
Specifies whether the A, B, C, and D matrices that are calculated are to be written out in OML format or not. Select from True and False.
The default is oml = True.
matlab
Bool
Specifies whether the A, B, C, and D matrices that are calculated are to be written out to a file that can be read by MATLAB. Select from True and False.
The default is matlab = False.
eigensol
Bool
Specifies whether the eigenvalue and eigenvector data is to be written to an .eig file. Select from True and False.
The default is eigensol = False
nodamping
Bool
Specifies whether the linearization solver should disable damping from all force elements for the eigenvalue solution.
The default is False; damping is considered for the eigenvalue solution.
kinetic
Bool
Specifies whether the modal kinetic energy distribution is to be written out to the solver log file and the *_linz.mrf output file. Select from True and False.
The default is kinetic = False
statemat
Bool
Specifies whether the A, B, C, and D matrices are to be calculated and written out into a file. The format of the file is determined by other attributes. Supported formats are OML, MDL MATLAB, and Simulink. Select from True and False.
The default is statemat = False
pinput
Reference to an existing plant input.
Specifies a plant input to be used for the State Space representation of the system. pinput participates in the B and D state matrices.
poutput
Reference to an existing plant output.
Specifies a plant output to be used for the State Space representation of the system. poutput participates in the C and D state matrices.
pstate
Reference to an existing plant state.
Specifies a plant state to be used in the state space representation of the system. A PlantState defines a list of user-defined states used in generating a linear representation of a model about an operating point. The linear representation is used for both eigenvalue analysis and state matrix generation.
cutoff_frequency
Double
Specifies the upper bound of the eigenvalues which are the natural frequency/damping characteristics of the system.

## Example

XML syntax versus Python for the same example:
  Linear(animation_scale = 1.0, simulink_mdl = False, matlab = False, eigensol = True, kinetic = True)