Variable and Values¶

• Every varibales in python are object
• Every variable assginment is reference based, that is, each object value is the reference to memory block of data

In [4]:

# a,b refer to the same memory location
a = 123
b = a  
print ('Data of a =',a,'\nData of b =',b)
print ('ID of a = ', id(a))
print ('ID of b = ',id(b))

Data of a = 123 
Data of b = 123
ID of a =  1867608032
ID of b =  1867608032

Changing data value (using assignment) actually changed the reference value

In [5]:

a = 123
b = a
a = 456  # reassignemnt changed a memory reference
         # b memory reference not changed
print ('Data of a =',a,'\nData of b =',b)
print ('ID of a = ', id(a))
print ('ID of b = ',id(b))

Data of a = 456 
Data of b = 123
ID of a =  3036866689104
ID of b =  1867608032