How to create SWIG typemap for a function that takes 2 tables?

Question

I'm trying to create a SWIG typemap for the following function:

void mix(int size, float *in1, float *in2, float *out1)
{
    for (int i = 0; i < size; ++i)
        out1[i] = in1[i] + in2[i];
}

In lua, I want this function to take 2 table arguments and return 1 table like the following:

local t = m.mix({1,2,3}, {4,5,6})

Then the table t should be {5,7,9} which is sum of the two tables.

I tried to use built-in typemaps but I could only wrap a function that takes and returns one table which is the following:

%apply (float *INOUT, int) {(float *inout, int size)};

How can I create a SWIG typemap for a function that takes two tables and returns one table?

Answer 1

I found a simple way to do it.

%apply (float *INOUT, int) {(float *in1, int n1)};
%apply (float *INPUT, int) {(float *in2, int n2)};

It seems to work fine for my purpose.