Hi Jan,
Using const in C++ MEX files can make your code safer and sometimes more efficient.
Why Use const?
It signals that a variable won't change, which improves readability and helps prevent bugs, while allowing the compiler to optimize your code, though the impact on performance may be minor.
For the “Initialize” function, pass “TypedArray” objects by reference to avoid unnecessary copying. Use “const TypedArray<double>&” if you don't plan to modify them. This is crucial in MEX functions since we may deal with large datasets and reducing memory operations can boost performance.
Here's an example of how you can define the “Initialize” function to efficiently handle “TypedArray” objects by using “const” references.
#include "mex.hpp"
#include "mexAdapter.hpp"
using namespace matlab::data;
using matlab::mex::ArgumentList;
class MexFunction : public matlab::mex::Function {
ArrayFactory factory;
public:
void operator()(ArgumentList outputs, ArgumentList inputs) {
// Assuming inputs[0] is a TypedArray<double> that we want to sum
double sm = 0;
const TypedArray<double> inArray = inputs[0];
for (auto& elem : inArray) {
sm += elem;
}
outputs[0] = factory.createScalar(sm);
// Call Initialize with inputs[1] and inputs[2]
Initialize(inputs[1], inputs[2]);
}
private:
void Initialize(const TypedArray<double>& x, const TypedArray<double>& y) {
// Example logic using x and y
// Since x and y are passed as const references, they cannot be modified
for (auto& elem : x) {
// Do something with elem, but don't modify x
}
for (auto& elem : y) {
// Do something with elem, but don't modify y
}
}
};
Hope this helps!
