Be careful with pass by reference and pass by value in Python



In [13]:

    
a = 1
b = a
b +=  1
print 'a = ', a
print 'b = ', b

When you assign a variable to another array in numpy, the new numpy arrays uses the same memory reference



In [14]:

    
import numpy as np
A = np.array(1)
B = A
B += 1
print 'A = ', A
print 'B = ', B



In [15]:

    
import numpy as np
A = np.array(1)
B = A.copy()
B += 1
print 'A = ', A
print 'B = ', B



In [ ]: