wehub-resource-sync
36 lines
721 B
Python
36 lines
721 B
Python
# coding:utf-8
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import numpy as np
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import scipy.spatial.distance as dist
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class Linear(object):
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def __call__(self, x, y):
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return np.dot(x, y.T)
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def __repr__(self):
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return "Linear kernel"
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class Poly(object):
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def __init__(self, degree=2):
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self.degree = degree
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def __call__(self, x, y):
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return np.dot(x, y.T) ** self.degree
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def __repr__(self):
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return "Poly kernel"
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class RBF(object):
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def __init__(self, gamma=0.1):
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self.gamma = gamma
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def __call__(self, x, y):
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x = np.atleast_2d(x)
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y = np.atleast_2d(y)
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return np.exp(-self.gamma * dist.cdist(x, y) ** 2).flatten()
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def __repr__(self):
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return "RBF kernel"
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