Introduction to Python functions: usage and examples of round function

Introduction to Python functions: Usage and examples of round function

Overview:
In Python, round() is a built-in function used to perform operations on numbers. rounding. It can round floating point or integer values ​​to a specified number of decimal places. The round() function has the following syntax:
round(number, ndigits)
where number is the number to be rounded, and ndigits is the number of decimal places to be retained.

Usage examples:

1. Rounding to integers
   If the ndigits parameter is 0 or omitted, a floating point number or integer can be rounded to the nearest integer value.

num1 = 10.4
num2 = 10.6

print(round(num1))  # 输出：10
print(round(num2))  # 输出：11

2. Round to the specified number of decimal places
   If the ndigits parameter is a positive integer, a floating point number or integer can be rounded to the specified number of decimal places.

num = 3.1415926

print(round(num, 2))  # 输出：3.14
print(round(num, 4))  # 输出：3.1416

3. Rounding to negative digits
   If the ndigits parameter is a negative integer, a floating point number or integer can be rounded to the specified number of digits, that is, the number of digits to the left of the decimal point.

num = 9876

print(round(num, -1))  # 输出：9900
print(round(num, -2))  # 输出：9800

Some notes:

1. The round() function returns a floating point number, even if the integer is passed in.
2. When the number to be rounded is equidistant from two integers, the round() function returns the nearest even integer.

num1 = 2.5
num2 = 3.5

print(round(num1))  # 输出：2
print(round(num2))  # 输出：4

Conclusion: The
round() function is a very useful function that can be used to round numbers. It can be rounded to an integer or to a specified number of decimal places. In some cases, it can also be used to round a number to a specified number of negative digits. Whether you are dealing with financial data, scientific calculations, or other scenarios that require precise processing of numbers, the round() function can come in handy.

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