MATLAB: How to change the variable name of “to workspace” dynamically

matlab/simulink

My question was showed in a picture. https://www.opendrive.com/files/?Ml8yOTY2NjJfa0Z4Z3E fig1 is a block I have established.fig2 is the input panel(NUM).In a system I need many A block,but has a"To Workspace"in A will error. I hope if I give a NUM is "1" ,the "To Workspace" can change its Variable name into "A_out1" automatically,and if the NUM input is "2" it can be changed into "A_out2".

Best Answer

I would recommend you go back to your previous question and follow the advice regarding data logging. My comment regarding "mask parameter could be a workaround" is really for the sake of argument. Your approach of putting a "To Workspace" block inside a customized library block is non-typical. It can be made to work with mask parameter but it is a stretch.

However, to prove it can be done, I'll show you the method here. Still, I strongly recommend that you use other data logging method. The worst case, is that you can choose not to put the "To Workspace" block inside the customized library block. Rather, you can put the "To Workspace" block outside of the reference block in the model.

Assume you added a mask parameter called 'VarNum' which is an 'edit' type, and the name of the "To Workspace" block inside is still called "To Workspace", you can add the following line in the "Dialog callback" of the mask parameter 'VarNum'.

set_param([gcb,'/To Workspace'],'VariableName',['A_Out',get_param(gcb,'VarNum')]);

Related Solutions

MATLAB: How to avoid variable (or file) name conflicts when using multiple copies of library subsystems with To Workspace (or To File) blocks

This conflict can be resolved by creating a mask for the subsystem block in the library itself. The following example demonstrates this.

Suppose that you have a library subsystem block that contains a To Workspace block whose variable name is "simout".

In your library, create a Mask for the subsystem block by right-clicking on the block and selecting 'Mask Subsystem'. Create a mask parameter for the mask and let this be the variable name that the To Workspace block inside will take, e.g.:

 Mask Prompt: 'Variable Name'
 Variable: simout

Now, click on click on the 'Initialization' tab of the Mask Editor and add the following statement to the initialization commands to set the variable name to the specified name in the mask. Also, check the option 'Allow library block to modify its contents'.

set_param([gcb,'/To Workspace'], 'VariableName', simout)

This will ensure that when the value of this parameter is changed, the above initialization will be executed and it will change the variable name for the To Workspace block within the subsystem accordingly. Note that the library link is intact while this is done.

When you use two or more copies of this library block in your model, you open up the mask dialog for this block and choose the variable name that you would like the To Workspace block to use. As long as you provide different names for all the copies of this subsystem in your mode, the naming conflict is resolved.

MATLAB: How to parametrize the “To Workspace” block in Simulink

Hi Krishnanand,

Since the variable name does not change during the simulation, you can set the output parameter 'VariableName' of the 'To Workspace' block completely from the base workspace like this:

First, you will need to get the system path for the 'To Workspace' block in question. You can do this interactively by selecting that block and then typing:

>> h = gcb;

or you can do this at the cmd prompt by typing:

>> h = find_system(gcs,'Name','To Workspace')

Where 'To Workspace' is the exact name of the block you want to manipulate. If you have more than one 'To Workspace' block, make sure to pick the right one!

Either way, the system path for the block will not change unless you change it, so you will only need to do this once after you create your model.

Then, before you start your simulation, just execute the following lines:

>> B.Label = 'test_struct_name';
>> set_param(h,'VariableName',B.Label);

Then you shoudld be good to go!

Best Answer

Related Solutions

MATLAB: How to avoid variable (or file) name conflicts when using multiple copies of library subsystems with To Workspace (or To File) blocks

MATLAB: How to parametrize the “To Workspace” block in Simulink

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