euclidean.py 文件源码

def make_spiral(self, r=0.25, G=0.0001):
        for k in range(10):
            x = self.X[:, 0] - 0.5
            y = self.X[:, 1] - 0.5
            theta = np.arctan2(x, y)
            ds = [r * (i + theta / (2 * np.pi)) for i in range(int(1 / r))]
            alphas = [np.sqrt(x ** 2 + y ** 2) / d for d in ds]
            for alpha in alphas:
                d = np.concatenate([(x * (1 - alpha))[:, None], (y * (1 - alpha))[:, None]], axis=1)
                f = -G * d / (d ** 2).sum(axis=1, keepdims=True)
                self.X += f
            self.X = np.clip(self.X, 0, 1)

        rs = np.arange(0, 0.7, 0.001)
        theta = 2 * np.pi * rs / r
        y = rs * np.sin(theta) + 0.5
        x = -rs * np.cos(theta) + 0.5
        spiral = zip(x, y)
        self.collection = matplotlib.collections.LineCollection([spiral], colors='k')