Before revision: The most correct and accurate methods for calculating the fractional integral require a record of all previous history, and therefore would require a constant space complexity solution O(n), where n is the number of samples measured for the complete history.
After revision: The most correct and accurate methods for calculating the fractional integral require a record of all previous history, and therefore would require a linear space complexity solution O(n), where n is the number of samples measured for the complete history.