recurrence.py 文件源码

def __init__(self, list_of_poly, parent):
        # the parent ring for this operator
        # must be an RecurrenceOperatorAlgebra object
        self.parent = parent
        # sequence of polynomials in n for each power of Sn
        # represents the operator
        # convert the expressions into ring elements using from_sympy
        if isinstance(list_of_poly, list):
            for i, j in enumerate(list_of_poly):
                if isinstance(j, int):
                    list_of_poly[i] = self.parent.base.from_sympy(S(j))
                elif not isinstance(j, self.parent.base.dtype):
                    list_of_poly[i] = self.parent.base.from_sympy(j)

            self.listofpoly = list_of_poly
        self.order = len(self.listofpoly) - 1