Target Language Compiler Function Conventions - MATLAB & Simulink (original) (raw)

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You can find examples using these functions in [_matlabroot_/toolbox/simulink/blocks/tlc_c](https://mdsite.deno.dev/matlab:cd%28[matlabroot%20'/toolbox/simulink/blocks/tlc%5Fc']%29;) and [_matlabroot_/toolbox/simulink/sfuntemplates/tlc_c](https://mdsite.deno.dev/matlab:cd%28[matlabroot%20'/toolbox/simulink/sfuntemplates/tlc%5Fc']%29;). The corresponding MEX S-function source code is located in [_matlabroot_/simulink/src](https://mdsite.deno.dev/matlab:cd%28[matlabroot%20'/simulink/src']%29;) or [_matlabroot_/toolbox/simulink/simdemos/simfeatures/src](https://mdsite.deno.dev/matlab:cd%28[matlabroot%20'/toolbox/simulink/simdemos/simfeatures/src']%29;). MATLAB® file S-functions and the MEX-file executables (for example,_`sfunction`_.mex*) are located in[_matlabroot_/toolbox/simulink/blocks](https://mdsite.deno.dev/matlab:cd%28[matlabroot%20'/toolbox/simulink/blocks']%29;) or[_matlabroot_/toolbox/simulink/simdemos/simfeatures](https://mdsite.deno.dev/matlab:cd%28[matlabroot%20'/toolbox/simulink/simdemos/simfeatures']%29;).Clicking one of the preceding folder names changes to that folder in MATLAB Files panel and shows the folder contents in the MATLAB Files panel.

Common Function Arguments

Several functions take similar or identical arguments. To simplify the reference pages, some of these arguments are documented in detail here instead of in the reference pages.

Argument Description
portIdx Refers to an input or output port index, starting at 0. For example, the first input port of an S-function is 0.
ucv User control variable. This is an advanced feature that overrides thelcv and sigIdx parameters. When used within an inlined S-function, it should generally be specified as"".
lcv Loop control variable. This is generally generated by the%roll directive via the second %roll argument (e.g., lcv=RollThreshold) and should be passed directly to the library function. It contains either "", indicating that the current pass through the %roll is being inlined, or it is the name of a loop control variable such as"i", indicating that the current pass through the%roll is being placed in a loop. Outside the%roll directive, this is usually specified as"".
sigIdx_or_idx Signal index. Sometimes referred to as the signal element index. When accessing specific elements of an input or output signal directly, the call to the various library routines should have ucv="",lcv="", and sigIdx equal to the desired integer signal index starting at 0. For complex signals, sigIdx can be an overloaded integer index specifying both whether the real or imaginary part is being accessed and which element. When you access these items inside a%roll, use the sigIdx generated by the%roll directive.Most functions that take asigIdx argument accept it in an overloaded form, wheresigIdx can beAn integer, e.g., 3. If the referenced signal is complex, then this refers to the identifier for the complex container. If the referenced signal is not complex, then this refers to the identifier.An id-num, usually of the form (see Overloading sigIdx)"%%" (e.g.,"re3"). The real part of the signal element. Usually"%%" whensigIdx is generated by the %roll directive."%%" (e.g.,"im3"). The imaginary part of the signal element or"" if the signal is not complex. Usually"%%" whensigIdx is generated by the %roll directive.Use the idx name when referring to a state or work vector.Functions that accept the three argumentsucv, lcv, sigIdx (oridx) are called differently depending upon whether or not they are used within a %roll directive. If they are used within a %roll directive, ucv is generally specified as "" and, lcv andsigIdx are the same as those specified in the %roll directive. If they are not used within a %roll directive, ucv andlcv are generally specified as "", andsigIdx specifies the index to access.
paramIdx Parameter index. Sometimes referred to as the parameter element index. The handling of this parameter is very similar to sigIdx above: it can be #, re#, orim#.
stateIdx State index. Sometimes referred to as the state vector element index. It must evaluate to an integer where the first element starts at0.

Overloading sigIdx

The signal index (sigIdx sometimes written as idx) can be overloaded when passed to most library functions. Suppose you are interested in element 3 of a signal, and ucv="", lcv="". The following table shows

Note that “container” in the following table refers to the object that encapsulates both the real and imaginary parts of the number, e.g.,creal_T, defined in [tmwtypes.h](https://mdsite.deno.dev/matlab:edit%28fullfile%28matlabroot,'extern',%20'include',%20'tmwtypes.h'%29%29).

sigIdx Complex Function Returns Example Data Type
"re3" Yes Real part of element 3 u0[2].re real_T
"im3" Yes Imaginary part of element 3 u0[2].im real_T
"3" Yes Complex container of element 3 u0[2] creal_T
3 Yes Complex container of element 3 u0[2] creal_T
"re3" No Element 3 u0[2] real_T
"im3" No "" N/A N/A
"3" No Element 3 u0[2] real_T
3 No Element 3 u0[2] real_T

Now suppose the following:

  1. You are interested in element 3 of a signal.
  2. (ucv = "i" AND lcv == "") OR (ucv = "" AND lcv = "i").

The following table shows values of idx, whether the signal is complex, and what the function that uses idx returns.

sigIdx Complex Function Returns
"re3" Yes Real part of element i
"im3" Yes Imaginary part of element i
"3" Yes Complex container of element i
3 Yes Complex container of element i
"re3" No Element i
"im3" No ""
"3" No Element i
3 No Element i

Notes

See Also

Topics