def _cholesky_sparse(self):
        """Algorithm for numeric Cholesky factorization of a sparse matrix."""
        Crowstruc = self.row_structure_symbolic_cholesky()
        C = self.zeros(self.rows)
        for i in range(len(Crowstruc)):
            for j in Crowstruc[i]:
                if i != j:
                    C[i, j] = self[i, j]
                    summ = 0
                    for p1 in Crowstruc[i]:
                        if p1 < j:
                            for p2 in Crowstruc[j]:
                                if p2 < j:
                                    if p1 == p2:
                                        summ += C[i, p1]*C[j, p1]
                                else:
                                    break
                            else:
                                break
                    C[i, j] -= summ
                    C[i, j] /= C[j, j]
                else:
                    C[j, j] = self[j, j]
                    summ = 0
                    for k in Crowstruc[j]:
                        if j < k:
                            summ += C[j, k]**2
                        else:
                            break
                    C[j, j] -= summ
                    C[j, j] = sqrt(C[j, j])

        return C
dataset/ETHPy150Open sympy/sympy/sympy/matrices/sparse.py/SparseMatrix._cholesky_sparse/swapped operands of `<`