inline T euclidean_distance()

in src/annoylib.h [192:202]

• 10 lines of code
• 2 McCabe index (conditional complexity)

inline T euclidean_distance(const T* x, const T* y, int f) {
  // Don't use dot-product: avoid catastrophic cancellation in #314.
  T d = 0.0;
  for (int i = 0; i < f; ++i) {
    const T tmp=*x - *y;
    d += tmp * tmp;
    ++x;
    ++y;
  }
  return d;
}