Numpy¶
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import numpy as np
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x = np.arange(10)
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x
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x + 1
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(x + 1)**2
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np.sin(x)
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np.sin(x).dtype
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x > 3
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x[:4]
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x[7:]
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x[x > 3]
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x[(x > 3) & (x < 7)]
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x[(x > 7) | (x < 3)]
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np.arange(50)
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np.arange(50).reshape(10,5)
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table = _
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table
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table**2
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(table**2)[2:4]
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(table**2)[:,2:4]
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(table**2)[5:7, 2:4]
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table ** 2 == 1089
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[index for (index, value) in np.ndenumerate(table**2) if value == 1089]
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l = list(range(10))
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l
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[i * 2 for i in l if i < 5]
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table**100
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a = np.mat('4 3; 2 1')
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b = np.mat('1 2; 3 4')
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a**2
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a
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a*b
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(np.arange(4)+1).reshape(2,2)
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np.mat(_)
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