A for loop allows you to iterate over a sequence of elements, such as a list, tuple, string, or range. It is useful for performing repetitive tasks on each item in a sequence.
Basic For Loop
The basic syntax of a for loop is as follows:
Explanation of Code:
The for loop iterates over each item in the sequence, executing the indented block of code for each item.
for item in sequence: # Code to be executedExplanation of Code:
In this example, the loop prints each fruit in the fruits list.
fruits = ["apple", "banana", "cherry"]for fruit in fruits: print(fruit)Looping Through a String
You can use a for loop to iterate over each character in a string.
Explanation of Code:
The loop iterates over each character in the string and executes the code block for each character.
text = "Hello"for char in text: print(char)Looping Through a Range
The range() function generates a sequence of numbers, which can be used to control the number of times a loop executes.
Explanation of Code:
The range() function creates a sequence of numbers from 0 up to (but not including) the specified end value. In this example, the loop prints numbers from 0 to 4.
for i in range(5): print(i)Looping with an Else Clause
You can include an else clause with a for loop. The else block will be executed after the loop finishes iterating over all items in the sequence.
Explanation of Code:
The else block runs after the loop completes normally.
for i in range(5): print(i)else: print("Loop is finished")Breaking out of a For Loop
You can use the break statement to exit a for loop prematurely, even if there are more items to iterate over.
Explanation of Code:
In this example, the loop prints numbers from 0 to 4 and then exits when i is equal to 5. The break statement immediately terminates the loop.
for i in range(10): if i == 5: break print(i)Skipping Iterations in a For Loop
The continue statement skips the current iteration and moves to the next iteration of the loop.
Explanation of Code:
In this example, the loop prints only odd numbers from 0 to 9. The continue statement allows you to skip specific iterations based on a condition.
for i in range(10): if i % 2 == 0: continue print(i)Nested For Loops
You can nest for loops within each other to iterate over multi-dimensional data structures.
Explanation of Code:
This example prints each item in a 2D list (matrix) in a structured format. Nested for loops allow you to iterate over each item in a multi-dimensional sequence.
matrix = [ [1, 2, 3], [4, 5, 6], [7, 8, 9]]for row in matrix: for item in row: print(item, end=" ") print()Python For Loops Example Code
Explanation of Code:
This program uses for loops to iterate over lists, strings, ranges, and demonstrates breaking out of loops, skipping iterations, and nesting loops.
# Basic for loopfruits = ["apple", "banana", "cherry"]for fruit in fruits: print(fruit)# Looping through a stringtext = "Hello"for char in text: print(char)# Looping through a rangefor i in range(5): print(i)# Looping with an else clausefor i in range(5): print(i)else: print("Loop is finished")# Breaking out of a for loopfor i in range(10): if i == 5: break print(i)# Skipping iterations in a for loopfor i in range(10): if i % 2 == 0: continue print(i)# Nested for loopsmatrix = [ [1, 2, 3], [4, 5, 6], [7, 8, 9]]for row in matrix: for item in row: print(item, end=" ") print()
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