How to define the data type of the input port data by ''ssGetOut​putPortRea​lSignal'' ?

In the S-function, the default data type of the output port is SS_DOUBLE. I want to define     the data type to SS_SINGLE.I write the lines as follows,but the displaying of the output data is error！I want to know why the result is wrong and I should how to define the data type.
Thank you!

static void mdlOutputs(SimStruct *S, int_T tid) { real32_T *y1 = ssGetOutputPortRealSignal(S,0); real_T *y2 = ssGetOutputPortRealSignal(S,1);

    int_T  in1        = ssGetInputPortWidth(S,0);
    int_T  in2        = ssGetInputPortWidth(S,1);
    int_T  in3        = ssGetInputPortWidth(S,2);

    InputPtrsType  x  = ssGetInputPortRealSignalPtrs(S,2);

    real32_T  *value_y = x[0]; 
    y1[0] = value_y[0] ;
    y1[1] = in2;
    y1[2] = in3;

    y2[0] = in1;
    y2[1] = in2;

}