Why Does get_param(​gcb,Compil​edPort*) Return Weird Results for Several Object Parameters ?

I have the following very simple model that has been compiled and simulated in Normal mode

Verify the Constant block is selected

>> gcb

ans =

    'mymodel/Constant'

Now try to access several Common Block Properties of the Constant block:

This looks incorrect.

>> get_param(gcb,'CompiledPortComplexSignals')

ans = 

  0×0 empty struct array with fields:

    Inport
    Outport
    Enable
    Trigger
    State
    LConn
    RConn
    Ifaction
    Reset
    Event

According to the linked doc page above, these parameters should be "properties common to all Simulink® blocks."

>> get_param(gcb,'CompiledPortDesignMin')
Constant block does not have a parameter named 'CompiledPortDesignMin'
 
>> get_param(gcb,'CompiledPortDesignMin')
Constant block does not have a parameter named 'CompiledPortDesignMin'

This looks incorrect.

>> get_param(gcb,'CompiledPortDimensions')

ans = 

  0×0 empty struct array with fields:

    Inport
    Outport
    Enable
    Trigger
    State
    LConn
    RConn
    Ifaction
    Reset
    Event

According to the linked doc page above, this parameter should be "properties common to all Simulink® blocks."

>> get_param(gcb,'CompiledPortDimensionsMode')
Constant block does not have a parameter named 'CompiledPortDimensionsMode'

This looks incorrect.

>> get_param(gcb,'CompiledPortFrameData')

ans = 

  0×0 empty struct array with fields:

    Inport
    Outport
    Enable
    Trigger
    State
    LConn
    RConn
    Ifaction
    Reset
    Event

This looks incorrect

>> get_param(gcb,'CompiledPortWidths')

ans = 

  0×0 empty struct array with fields:

    Inport
    Outport
    Enable
    Trigger
    State
    LConn
    RConn
    Ifaction
    Reset
    Event

Can anyone explain these results?

Answer 1

[Paul]

Thanks to @Andy Bartlett discussion in this thread, and further review the doc, the model has to be put into compile mode before accessing the Compiled* block parameters. But there still seems to be inconsistency for some parameters between what's actually returned and what the doc says should be returned.

Here is the model:

Verify the Integrator is the current block

gcb
ans = 'test/Integrator'

Compile the model. The use of feval in the workflow for accessing Compiled* is block properties is shown on the Common Block Properties doc page, but only for some Compiled* properties.

feval(gcs, [],[],[],'compile');

Now try to access several Common Block Properties of the Integrator block.

According to the Common Block Properties doc page linked above, these parameters should be "properties common to all Simulink® blocks." But they are not.

try
    DesignMin      = get_param(gcb,'CompiledPortDesignMin')
catch
    disp('Invalid block parameter: CompiledPortDesignMin');
end

Invalid block parameter: CompiledPortDesignMin

try
    DimensionsMode = get_param(gcb,'CompiledPortDimensionsMode')
catch
    disp('Invalid block parameter: CompiledPortDimensionsMode');
end

Invalid block parameter: CompiledPortDimensionsMode

These properties are really properties of the ports of the block, not the block itself. This approach to getting these port properties is documented on the linked doc page, but I'm not sure why they are shown as block properties.

ports = get_param(gcb,'PortHandles');
DesignMin = get_param(ports.Outport, 'CompiledPortDesignMin')

DesignMin =

[]

But, DesignMin is supposed to be returned as a structure.

DimensionsMode = get_param(ports.Outport, 'CompiledPortDimensionsMode')

DimensionsMode =

0

ComplexSignals = get_param(gcb,'CompiledPortComplexSignals')

ComplexSignals = struct with fields:

Inport: 0

Outport: 0

Enable: []

Trigger: []

State: []

LConn: []

RConn: []

Ifaction: []

Reset: []

Event: []

PortDimensions = get_param(gcb,'CompiledPortDimensions')

PortDimensions = struct with fields:

Inport: [1 1]

Outport: [1 1]

Enable: []

Trigger: []

State: []

LConn: []

RConn: []

Ifaction: []

Reset: []

Event: []

However, PortDimensions is supposed to be returned as a numeric array.

FrameData      = get_param(gcb,'CompiledPortFrameData')

FrameData = struct with fields:

Inport: 0

Outport: 0

Enable: []

Trigger: []

State: []

LConn: []

RConn: []

Ifaction: []

Reset: []

Event: []

PortWidths     = get_param(gcb,'CompiledPortWidths')

PortWidths = struct with fields:

Inport: 1

Outport: 1

Enable: []

Trigger: []

State: []

LConn: []

RConn: []

Ifaction: []

Reset: []

Event: []

Set the model to term

feval(gcs, [],[],[],'term');

Is the use of the model name as a function documented anywhere? I can't find it.

[Fangjun Jiang]

@Paul, is this what you are looking for?

https://www.mathworks.com/help/simulink/ug/simulink-model-command.html

[Paul]

Yes, I think so. Never in a millenia would I have thought to look for it at that location in the doc.