In [3]:

    

import numpy as np


    

In [12]:

    

x1 = np.array([1.,2.,3.])
x2 = np.array([4.,5.,6.])
x1.dot(x2)


    

    
Out[12]:





32.0

In [14]:

    

x1 = np.array([1.,2.,3.])
x2 = np.array([7.,　8.,　9., 10.])
x1.dot(x2)


    

    




  File "<ipython-input-14-2483e7310712>", line 2
    x2 = np.array([7.,　8.,　9., 10.])
                      　^
SyntaxError: invalid character in identifier

In [16]:

    

def _squared(n):
    return np.power(2., np.arange(1 , n + 1., 1) * -1)

def _sin(n):
    return np.sin(np.pi * 3. * np.arange(1 , n + 1., 1) / 2.)

x1 = _squared(3.)
x2 = _sin(3.) * 3

x1.dot(x2)


    

    
Out[16]:





-1.1249999999999998

In [31]:

    

a = np.array([1., 2., 3.])
b = np.array([4., 5., 6.])
1 / (1+np.exp(-30))


    

    
Out[31]:





0.99999999999990652

In [33]:

    

a * 3


    

    
Out[33]:





array([ 3.,  6.,  9.])

In [ ]:

    

np.linspace()