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