Imports

Imports are the mechanism which make it possible to bring functionality from other Python libraries into your own code.



In [1]:

    
from math import pi, sin

The above expression brings in pi and sin from the math library.



In [2]:

    
pi # The constant pi









    Out[2]:





3.141592653589793



In [3]:

    
sin(pi*1/2.) # The function sin









    Out[3]:





1.0

You can also just import a library and not any particular function.



In [4]:

    
import math
math.e









    Out[4]:





2.718281828459045

Finally in some cases you want to import a library, but the name of the library makes it cumbersome to use in your code. You can specify the name which you want to use for the library as follows.



In [5]:

    
import math as m
m.e









    Out[5]:





2.718281828459045