Is there any way to ensure calculation precision?  [SOLVED]

Here I would like to introduce a piece of simple code to show precision loss when involving large number calculation:

//----- code begins -----

Vars: X(8121.2), Y(8339.3);

value1 = Power((X - Y), 4);
value2 = power(X, 4) - 4 * power(X, 3) * Y + 6 * power(X, 2) * Power(Y, 2) - 4 * X * Power(Y, 3) + Power(Y, 4);

once cleardebug;
once print(value1:1:20, NewLine, value2:1:20);
once (value1 - value2 <> 0) print((value1 - value2):1:20);

//----- end of code -----

the output is:

2262677521.11207720000000000000
2262677528.00000000000000000000
-6.88792276382446290000

apparently there is a discrepancy between value1 and value2 and the difference is -6.88792276382446290000. But they should be the same, since the formula of value2 is just an expansion of that of value1.

For some reasons I need to use formulae like that of value2 in my studies.

Has anybody encountered this problem? How do you avoid/solve it?

Thanks for your time.

Hello trazom,

You have reached the limit of precision for double type values in C++ which is 15 digits. (MSDN).
You can use MultiCharts .NET where decimal type that provides 28 digit precision can be used. (MSDN)