Root Mean Square Code Replacement

Open the programmatic interface from the MATLAB menu by selecting New > Function.

Create a table.

function hTable = crl_rms_func
% Create a function to call the code replacement library table 

%% Create a table object
hTable = RTW.TflTable;

Create an entry by calling the function createCRLEntry. Specify these arguments:

For this example, replace the code for rms functions that perform the calculation over the entire input of a three-dimensional matrix with the custom function rms_all.

function hTable = crl_rms_func
% Create a code replacement library table 

%% Create a table object
hTable = RTW.TflTable;

%% Create an entry
hEntry = createCRLEntry(hTable,...
                      "single y1 = rms(single u1[1 1 1; inf inf inf])",...
                      "single y1 = rms_all(single* u1)");

Create entry parameters. Because this example replaces a function, create entry parameters by calling the function setTflCFunctionEntryParameters. For this example, specify the implementation header file rms_all.h.

function hTable = crl_rms_func
% Create a code replacement library table 

%% Create a table object
hTable = RTW.TflTable;

%% Create an entry
hEntry = createCRLEntry(hTable,...
                      "single y1 = rms(single u1[1 1 1; inf inf inf])",...
                      "single y1 = rms_all(single* u1)");

%% Create entry parameters
hEntry.setTflCFunctionEntryParameters("ImplementationHeaderFile","rms_all.h");

Add the entry to the table by calling addEntry.

function hTable = crl_rms_func
% Create a code replacement library table 

%% Create a table object
hTable = RTW.TflTable;

%% Create an entry
hEntry = createCRLEntry(hTable,...
                      "single y1 = rms(single u1[1 1 1; inf inf inf])",...
                      "single y1 = rms_all(single* u1)");

%% Create entry parameters
hEntry.setTflCFunctionEntryParameters("ImplementationHeaderFile","rms_all.h");

%% Add entry to the table
addEntry(hTable,hEntry);

Validate and save the customization file. From the MATLAB menu, save this customization file by selecting File > Save. From the command line, validate the code replacement library table by calling it:

hTable = crl_rms_func

Register the code replacement library. Registration creates a code replacement library by defining the library name, code replacement tables, and other information. Create a registration file (a new function file) with these specifications:

function rtwTargetInfo(cm)
 
cm.registerTargetInfo(@loc_register_crl);
end
 
function this = loc_register_crl 
 
this(1) = RTW.TflRegistry; 
this(1).Name = 'CRLRMSFunc';
this(1).TableList = {'crl_rms_func.m'}; % table created in this example
this(1).TargetHWDeviceType = {'*'};
this(1).Description = 'Example code replacement library';

end

To use your code replacement library, refresh your current MATLAB session with the command:

RTW.TargetRegistry.getInstance('reset');

Verify the code replacement library. From the MATLAB command line, open the library by using the Code Replacement Viewer and verify that the table and entry are correctly specified. For more information, see Verify Code Replacement Library. Configure your model to use the code replacement library, generate code, and verify that code replacement occurs as expected. If unexpected behavior occurs, examine the hit and miss logs to troubleshoot the issues.

Refresh the current MATLAB^® session to make the code replacement library available by entering RTW.TargetRegistry.getInstance('reset'); at the command line.

RTW.TargetRegistry.getInstance('reset');

Create a code generation configuration that uses the code replacement library. You can also configure the code generator to generate a report that includes information on the code replacements.

cfg = coder.config('lib');
cfg.GenerateCodeReplacementReport = true;
cfg.CodeReplacementLibrary = "CRLRMSFunc";
cfg.GenCodeOnly = true;
cfg.GenerateReport = true;
cfg.InstructionSetExtensions="None";

Create an example three-dimensional input argument matrix.

A = rand(4,5,6);

Generate code for the wrapper function by using the configuration.

codegen -config cfg rmswrapper -args {A};