sqrt (float x)
{
  ...
}

sqrt (float64 x)
{
  ...
}

round (float x, int accuracy)
{
  ...
}

is_nan -a (numeric x)                                                          /* "if (value->is_nan ()) ..." */
      for (numeric : float, float64)
       -> (byte not_a_number = 0)
{
  ...
}

...

