Extended __fastcall Mean(const double * Data, const int Data_Size);
The Mean() function considers an array
of numbers and calculates the average value of those numbers. The function
takes two arguments. The first, Data, is the name of the array of numbers.
These number could integers or floating numbers. The second argument,
Data_Size represents the number-1 of members of the array. You can type
an integral number as the Data_Size or you can use the sizeof
operator to get the dimension of the array and subtract 1 from it. After the
calculation, the function returns a long double-precision number as the
average of the numbers.