Call C functions from Swift 4

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I’ve generated C code from MATLAB by using the codegen tool. The function can be described as follows:

function [result] = calculate_data(my_matrix)
    for idx = 1:length(my_matrix)
        result = result + sum(my_matrix(idx,1:3));
    end
end

When using the codegen tool, I explicitly stated that my_matrix is a type of double(:inf, 3). In other words, the number of rows is unbounded, but it will have 3 columns. When the code is generated, this is the function that is generated that I am to execute:

calculate_data(my_matrix : UnsafePointer<emxArray_real_T>!, result : UnsafeMutablePointer<emxArray_real_T>!)

emxArray_real_T is defined as follows in a different c file:

struct emxArray_real_T
{
  double *data;
  int *size;
  int allocatedSize;
  int numDimensions;
  boolean_T canFreeData;
};

When I see my initialization options for the above class, this one in particular makes sense:

emxArray_real_T.init(data: UnsafeMutablePointer<Double>!, size: UnsafeMutablePointer<Int32>!, allocatedSize: Int32, numDimensions: Int32, canFreeData: boolean_T)

I’ve tried to follow this document as a means to wrap my head around how to call the generated C code, but I think I might be missing a basic step. Here is what I am doing:

// create an 2d array with some fake data
var mySampleData = [[Double]]();
for i in 0 ..< 3 {
    mySampleData.append([1.1, 2.2, 3.3]);
}

// begin fulfilling requirements for emxArray_real_T
var data_pointer = UnsafeMutablePointer<Double>.allocate(capacity: 3);
data_pointer.initialize(from: mySampleData)

However, the above code throws an error stating that:

Generic parameter 'C' could not be inferred

I take it that I am then doing something completely wrong, and am probably on an incorrect path. There is a similar post that relates to my question, How to convert float[][] type array to "emxArray_real_T *x" , however the provided solution seems to be for C, as opposed to for Swift 4. How can I effectively call a C function using Swift 4, and meet the requirements of the emxArray_real_T.init method? Using fake data is ok to demonstrate the basic principle.

Source: Swift