Index Substructures and Fields

As in MATLAB®, you index substructures and fields structures in MATLAB Function blocks by using dot notation. However, for code generation from MATLAB, you must reference field values individually (see Structure Definition for Code Generation).

For example, in the emldemo_bus_structemldemo_bus_struct model described in Attach Bus Signals to MATLAB Function Blocks, the MATLAB function uses dot notation to index fields and substructures:

function [outbus, outbus1] = fcn(inbus)
%#codegen
substruct.a1 = inbus.ele3.a1;
substruct.a2 = int8([1 2;3 4]);

mystruct = struct('ele1',20.5,'ele2',single(100),
                  'ele3',substruct);

outbus = mystruct;
outbus.ele3.a2 = 2*(substruct.a2);

outbus1 = inbus.ele3;

The following table shows how the code generation software resolves symbols in dot notation for indexing elements of the structures in this example:

Dot NotationSymbol Resolution
substruct.a1Field a1 of local structure substruct
inbus.ele3.a1Value of field a1 of field ele3, a substructure of structure inputinbus
inbus.ele3.a2(1,1)Value in row 1, column 1 of field a2 of field ele3, a substructure of structure input inbus

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