from util import Object import numpy as np CURVE_LINSPACE = np.linspace(-10, 10, num=2000) DEFAULT_CURVE = (3, 3, 11) NSA_CURVE = (3, 0, 2**384 - 2**128 - 2**96 + 2**32 - 1) BTC_CURVE = (0, 7, 2**256 - 2**32 - 2**9 - 2**8 - 2**7 - 2**6 - 2**4 - 1) class EllipticCurve(Object): def __init__(self, a, b, mod): self.a = a self.b = b self.mod = mod self.xl = CURVE_LINSPACE self.yl = self._x2y() def _x2y(self): r = np.empty((self.xl.size, 2)) for i, xi in enumerate(self.xl): r[i][0] = np.sqrt((xi**3) + (self.a * xi**2) + self.b) for i in range(self.xl.size): r[i][1] = -r[i][0] return r def yfromx(self, x, is_top = True): r = np.sqrt((x**3) + (self.a * x**2) + self.b) r = +r if is_top else -r return r