Energy Grid Interpolation Rounding Error

[HunterBelanger]

Currently, it appears that round-off error is occurring when an EnergyGrid instance is constructed directly from an std::vector<double>, as it first converts all of the values to floats, and then saves them as doubles. This is a remnant of when I used to store XS data as floats. It should suffice to just pass the energy argument to the energy_values_ member in the class initialization, and remove the entire for loop at line 63.

papillon-ndl/src/energy_grid.cpp

Line 63 in 1fcaffc

energy_values_[i] = static_cast<float>(energy[i]);