Evaluating a Global Expression
Evaluate a global expression with the function mphglobal.
To evaluate a global expression at the MATLAB® prompt, call the function mphglobal as in this command:
[d1,...] = mphglobal(model,{'e1',...})
where e1,... are the COMSOL Multiphysics global expressions to evaluate. The output values d1,... are returned as a Px1 double array, with P the length of inner parameters.
The rest of this section has additional information for the function mphglobal:
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Specify the Evaluation Data
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Output Format
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Other Evaluation Properties
Specify the Evaluation Data
The function mphglobal supports the following properties to set the data of the evaluation to perform:
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dataset, specify the solution dataset to use in the evaluation:
data = mphglobal(model,<expr>,'dataset',<dsettag>)
<dsettag> is the tag of a solution dataset. The default value is the current solution dataset of the model.
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solnum, specify the inner solution number for data evaluation. Inner solutions are generated for the following analysis types: time domain, frequency domain, eigenvalue, or stationary with continuation parameters:
data = mphglobal(model,<expr>,'solnum',<solnum>)
where <solnum> is an integer array corresponding to the inner solution index. <solnum> can also be a string:'end' or 'all' to evaluate the expression for the last inner solution or all inner solutions, respectively. By default the evaluation is performed on all inner solutions.
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outersolnum, specify the outer solution number for data evaluation. Outer solutions are generated with parametric sweeps:
data = mphglobal(model,<expr>,'outersolnum',<outersolnum>)
where <outersolnum> is a positive integer corresponding to the outer solution index. <outersolnum> can also be a string, 'all' or 'end' to evaluate the expression for all or the last outer solution, respectively. The default settings uses the first outer solution for the data evaluation.
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To evaluate the expression data at a specific time use the property t:
data = mphglobal(model,<expr>,'t',<time>)
where <time> is a double array. The default value corresponds to all the stored time steps.
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phase, specify the phase in degrees:
data = mphglobal(model,<expr>,'phase',<phase>)
where <phase> is a double value.
Output Format
The function mphglobal also supports other output formats.
To extract the unit of the evaluated expression, define an extra output variable:
[data,unit] = mphglobal(model,<expr>)
with unit is a 1xN cell array where N is the number of expressions to evaluate.
Returns only the real part in the data evaluation with the property complexout:
data = mphglobal(model,<expr>,'complexout','off')
Other Evaluation Properties
Set the unit property to specify the unit of the evaluation:
data = mphglobal(model,<expr>,'unit',<unit>)
where <unit> is a cell array with the same length as <expr>.
Use the property matherr to return an error for undefined operations or expressions:
data = mphglobal(model,<expr>,'matherr','on')