Loops in Python explained with examples

This tutorial covers various ways to execute loops in python. Loops is an important concept of any programming language which performs iterations i.e. run specific code repeatedly until a certain condition is reached.

1. For Loop

Like R and C programming language, you can use for loop in Python. It is one of the most commonly used loop method to automate the repetitive tasks.

How for loop works?

Suppose you are asked to print sequence of numbers from 1 to 9, increment by 2.

for i in range(1,10,2):
  print(i)

Output

1
3
5
7
9

range(1,10,2) means starts from 1 and ends with 9 (excluding 10), increment by 2.

Iteration over list
This section covers how to run for in loop on a list.

mylist = [30,21,33,42,53,64,71,86,97,10]
for i in mylist:
    print(i)

Output

30
21
33
42
53
64
71
86
97
10

Suppose you need to select every 3rd value of list.

for i in mylist[::3]:
    print(i)

Output

30
42
71
10

mylist[::3] is equivalent to mylist[0::3] which follows this syntax style list[start:stop:step]

Python Loop Explained with Examples

Example 1 : Create a new

(continued...)

from Planet SciPy
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