mwArray structure index explaination

Hello I am a little bit confused about the documentation of mwArray. Let's say I have structure array like

const char *field_name[] = {"a", "b", "c", "d"};
mwArray structure(2,1,4,field_name);

the question is how can I set value to structure(1).a and structure(2).a respectively? what the index should be in structure.Get() function? Thanks!

Answer 1

[Adam]

I tend to use

mxCreateStructMatrix

to create a struct, but I guess your syntax works just as well, judging from the help. Then you can use either of these

mxSetFieldByNumber
mxSetField

to set a field e.g.

const char* axisFieldNames[] = { "x", "y", "z" };
mxArray* labelsStruct = mxCreateStructMatrix( 1, 1, 3, axisFieldNames );
mxSetFieldByNumber( labelsStruct, 0, 0, "someStringForX" );
mxSetFieldByNumber( labelsStruct, 0, 1, "someStringForY" );
mxSetFieldByNumber( labelsStruct, 0, 2, "someStringForZ" );

If you have an actual array of structs as you do then of course you will want to fill in values for indices other than 0 in the 2nd argument. In my code where I took this example from I was just creating a scalar struct.

[eey]

Hi, thanks for your reply, but I was talking about mwArray and the question was how to access different element if I have a structure array and set values for the same field in different elements.

[Adam]

Change the 2nd argument to mxSetField or mxSetFieldByNumber or mxGetFieldByNumber or mxGetField