diff options
Diffstat (limited to 'pyecsca/ec/divpoly.py')
| -rw-r--r-- | pyecsca/ec/divpoly.py | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/pyecsca/ec/divpoly.py b/pyecsca/ec/divpoly.py index 460b861..c92ef64 100644 --- a/pyecsca/ec/divpoly.py +++ b/pyecsca/ec/divpoly.py @@ -1,3 +1,6 @@ +""" +Provides functions for computing division polynomials and the multiplication-by-n map on an elliptic curve. +""" from typing import Tuple, Dict, Set, Mapping from sympy import symbols, FF, Poly @@ -167,10 +170,10 @@ def divpoly(curve: EllipticCurve, n: int, two_torsion_multiplicity: int = 2) -> """ Compute the n-th division polynomial. - :param curve: - :param n: - :param two_torsion_multiplicity: - :return: + :param curve: Curve to compute on. + :param n: Scalar. + :param two_torsion_multiplicity: Same as sagemath. + :return: The division polynomial. """ f: Poly = divpoly0(curve, n)[n] a1, a2, a3, a4, a6 = a_invariants(curve) @@ -199,7 +202,7 @@ def mult_by_n(curve: EllipticCurve, n: int) -> Tuple[Tuple[Poly, Poly], Tuple[Po :param curve: Curve to compute on. :param n: Scalar. - :return: + :return: A tuple (mx, my) where each is a tuple (numerator, denominator). """ xs, ys = symbols("x y") K = FF(curve.prime) @@ -208,7 +211,7 @@ def mult_by_n(curve: EllipticCurve, n: int) -> Tuple[Tuple[Poly, Poly], Tuple[Po Kxy = lambda r: Poly(r, xs, ys, domain=K) # noqa if n == 1: - return x + return x, y a1, a2, a3, a4, a6 = a_invariants(curve) |