You are probably looking at a rather mathematical sketch of an algorithm. There are two general roads to implement non-trivial mathematical expressions such as series, integrals, and differential equations.

1. If you want exact, potentially symbolic results you have to simplify "complex" expressions into closed forms on paper, and/or employ computer algebra.
2. If you are satisfied with numerical, potentiall approximate solutions you want to employ numerical algorithms, including error estimations.

You are probably looking at a rather mathematical sketch of an algorithm. There are two general roads to implement non-trivial mathematical expressions such as series, integrals, and differential equations.

1. If you want exact, potentially symbolic results you have to simplify "complex" expressions into closed forms on paper, and/or employ computer algebra.
2. If you are satisfied with numerical, potentially approximate solutions, you want to employ numerical algorithms, including error estimations.

You are probably looking at a rather mathematical sketch of algorithm. There are two general roads to implement such sketches.

1. If you want exact, potentially symbolic results you have to simplify "complex" expressions into closed forms on paper, and/or employ computer algebra.
2. If you are satisfied with approximate, numerical solutions you want to employ numerical algorithms, including error estimations.

You are probably looking at a rather mathematical sketch of an algorithm. There are two general roads to implement non-trivial mathematical expressions such as series, integrals, and differential equations.

1. If you want exact, potentially symbolic results you have to simplify "complex" expressions into closed forms on paper, and/or employ computer algebra.
2. If you are satisfied with numerical, potentiall approximate solutions you want to employ numerical algorithms, including error estimations.