In Python, the formatting expression %.2f is used to format floating-point numbers with two decimal places. This is an older method of string formatting that uses the % operator.
Here’s how you can use it:
# Example floating-point number
num = 3.1415926
# Using %.2f to format the number with two decimal places
formatted_num = "%.2f" % num
print(formatted_num) # Output: 3.14
In this example, %.2f is the format specifier. The % operator is used to insert the value of num into the format string while applying the specified formatting. The .2 indicates that we want to display two decimal places, and f is the type specifier for a floating-point number.
While the % operator formatting method is still valid in Python, the newer and more preferred way of string formatting is by using either the str.format() method or f-strings (available in Python 3.6 and above), which offer more flexibility and readability.
2f Python example
Here’s how you can achieve the same result using f-strings:
num = 3.1415926
formatted_num = f"{num:.2f}"
print(formatted_num)
Output:
Format strings:
# Example string
name = "John"
# Using f-string to format the string
greeting = f"Hello, {name}!"
print(greeting) # Output: Hello, John!
Format with variable width and alignment:
# Example numbers
num1 = 123
num2 = 45678
# Using f-string to format with variable width and alignment
formatted_num1 = f"Number 1: {num1:6d}" # Right-aligned, minimum width of 6 characters
formatted_num2 = f"Number 2: {num2:<10d}" # Left-aligned, minimum width of 10 characters
print(formatted_num1) # Output: Number 1: 123
print(formatted_num2) # Output: Number 2: 45678
Perform calculations inside f-strings:
# Example numbers
x = 10
y = 3
# Using f-string to perform calculations inside the string
result = f"{x} plus {y} is {x + y}, and {x} divided by {y} is {x / y:.2f}"
print(result)
# Output: 10 plus 3 is 13, and 10 divided by 3 is 3.33
F-strings offer great flexibility, allowing you to include expressions and perform various operations within the string, making them a powerful tool for string formatting in Python.
Note: IDE: PyCharm 2021.3.3 (Community Edition)
Windows 10
Python 3.10.1
All Python Examples are in Python 3, so Maybe its different from python 2 or upgraded versions.