Itertools module in python

Itertools module in Python Tutorial:The itertools is a module used to iterate the data structure that is used for loop. Here data structure is known as iterables also incorporates for a loop. The module is used to enhance maintainability of code. The module will implement iterator building the block by constructs from SML and Haskell. The SML will provide a tool: tabulate (f) that produces sequence as f (0), f (1)… The tool will be built-in counterpart and work with high-speed function. The module in python is a collection of tools for handling the iterators.

Example:-

 for each in colors:
   print (each) 

The need of importing the itertools module is impotent before using it.
We will import the operators module which not necessary while using itertools.
import itertools
import operatorThe python itertool is useful for creating the iterators.
The programs use iterator and present in the form of iteration.
The operations will manage the memory use of variables, size of sequence and create code use.
The module provides functions that work on iterators and produce complex iterators.
They will work fast and used to form iterator algebra.

Example:-

Import operator
Import time
L1= [1, 2, 3]
L2= [2, 3, 4]
T1=time. time ()
a, b, c=map (operator, mul, L1, L2)
t2=time. time ()
print (“Result:”a, b, c)
print(“Time taken by function: %.6f” %( t2-t1))
t1=time. time ()
print (“Result:”end=””)
for I in range (3):
print (L1 [i]*L2 [i], end=””)
t2=time. time ()
print (“\n time taken by”)
print (L1 [i]*L2 [i], end=””)
t2 = time. time ()
print ("\nTime: %.6f" %( t2 - t1))

Output:-

Result: 2 6 12
Time taken by map function: 0.000005
Result: 2 6 12
Time taken by map function: 0.000014

Types of iterators are:-

Infinite Iterators:-

They will include the cycle, count and repeat function.
It takes a function as count also has two arguments and a return an iterator.
Here count has the first argument as starting value and the second argument has increment step.
Example:-
Import itertools
Result=itertools.count (start=0, step=2)
For number in result:
If num<8:
Print (number)
Else:
Break:
Output:-
0
2
4

Repeat:-

 Here the function will take an iterable and iterates.
Cycle:-it goes through the iterable element at a time and repetition takes the whole iterable each time.
Repeat:-It will take the time parameter used for termination.
Example:-
Import itertools
Result=itertools.repeat (‘hello’, times=2)
For word in result:
Print (word)
Output:-
hello
hello

Finite Iterator:-

They will include the chain, compress, and dropwhile.
The function accepts variable number and loop through all one by one.
Example:-
Import itertools
List_one= [‘a’,’b’,’c’]
List_two= [‘d’,’e’,’f’]
List_three= [‘1’,’2’,’3’]
Result=itertools.chain (List_one, List_two, List_three)
For element in result:
Print (element)
Output:-
a
b
c
d
e
f
1
2
3