| Are a MATLAB programmer
with little or no C programming experience | A Level-2 MATLAB S-function,
especially if you do not need to generate code for a model containing
the S-function (see Writing S-Functions in MATLAB). |
| Need to generate code for a model containing the S-function | Either a Level-2 MATLAB S-function
or a C MEX S-functions. Level-2 MATLAB S-functions
require that you write a Target Language Compiler (TLC) file for your
S-function, before generating code. C MEX S-functions, however, automatically
support code generation. |
| Need the simulation to run faster | A C MEX S-function, even if you do not need to generate code
(see Writing S-Functions in C).
For complicated systems, Level-2 MATLAB S-functions
simulate slower than C MEX S-functions because they call out to the MATLAB interpreter. |
| Need to implement the S-function in C, but have no previous
experience writing C MEX S-functions | The S-Function Builder. |
| Are incorporating legacy code into the model | Any S-function, with the exception of a Level-1 MATLAB S-function. Consider using the
Legacy Code Tool if your legacy function calculates only outputs,
not dynamic states (see Integrating Existing C Functions into Simulink Models
with the Legacy Code Tool). Otherwise, consider using the S-Function Builder.
If you need to call the legacy code during simulation, do not use
a Level-2 MATLAB S-function
because they call legacy code only through their TLC files. |
| Need to generate embeddable code for an S-function that incorporates
legacy code | The Legacy Code Tool if your legacy function calculates only
outputs. Otherwise, use a handwritten C MEX S-function or the S-Function
Builder. |
