use block constructs to represent the algorithm, and create use cases for each of the functions used in the algorithm

use activity constructs to represent the algorithm and its functions, and create actions to represent the use of functions in the algorithm

use block constructs to represent the algorithm and its functions, and create part properties to represent the use of the functions in the algorithm

use activity constructs to represent the algorithm and its functions, and create containment relationships to represent the use of functions in the algorithm

use package constructs to represent the algorithm and its functions, and create containment relationships to represent the use of functions in the algorithm

Code generation is outside the scope of SysML. so the system engineer should use UML