For Loop in Python
In Python, the for
loop is used to iterate over a sequence (such as a list, tuple, string, or range) or any iterable object. Here's the basic syntax of a For
loop in Python:
pythonCopy codefor item in iterable:
# Code block to execute for each iteration
# You can use the 'item' variable to access the current element
# of the iterable
Here's a breakdown of how it works:
item
: This is a variable name that represents the current element in the iteration. You can choose any valid variable name here.iterable
: This is the object over which the loop iterates. It could be a list, tuple, string, dictionary, or any other iterable object.Indentation: In Python, indentation is crucial for defining blocks of code. The code block following the
for
statement is indented, typically by four spaces (or a tab), to indicate that it belongs to the loop.
Example 1: Iterating over a list:
pythonCopy codefruits = ["apple", "banana", "cherry"]
for fruit in fruits:
print(fruit)
Output:
apple
banana
cherry
Example 2: Iterating over a string:
pythonCopy codefor char in "hello":
print(char)
Output:
h
e
l
l
o
Example 3: Using range()
for a numerical loop:
pythonCopy codefor i in range(5):
print(i)
Output:
0
1
2
3
4
In this last example, range(5)
generates numbers from 0 to 4, and the loop iterates over these numbers, assigning each to the variable i
.
Remember, the for
loop can be used with any iterable object in Python, making it a versatile tool for iteration. Learn more with programs such as masters in data Science and free python tutorial online!