Test this please

leave some idea. We can technically generate constants using constexpr functions to avoid storing them in the source.

#include <cmath>
#include <iostream>

constexpr double foo(double a)
{
  double res = 0;
  for(int i=0;i<2;i++)
    res+= ::sin(a+i);
  return res;
}

int main()
{
  constexpr double b = foo(2); # can be evaluated at compile time even if it involves math function calls in it.
  std::cout << "b = " <<b <<std::endl;
  return b;
}

• Please post some of the data you have on the performance improvements with details of the system (basis etc.) and hardware. I do believe the result -- it is more than unrolling.

I added the data. Should I create tests for these or just the numbers as is are enough?

* Is this code a cut & paste from the cited article or do you have a generator code? If the latter we should capture it, just as we have been capturing Mark's python codes for optimization and wavefunction testing.

Yes There is a code generator. Kevin (@kgasperich ) will supply it.

* I hope we can get test coverage near 100% for these foundational numeric functions.

There is an existing test already covering this function but it is not clear if it is being called. Once the deadlines are past we will "clean" it.

Generator code should be added in case "we" end up redoing this.

Ping. What is the status/plan for this code?

To be merged this will need at least the generator code added, as previously requested, and -- similar to how Mark Dewing did this for other generated code -- suitably clear comment guards around the generated code. ( "DO NOT EDIT AUTOMATICALLY GENERATED BY XYZ.PY" ). Automagically generated unit tests would also be ideal -- we ought to be able to get ~100% coverage for these functions.