Python statistics fmean()

The statistics.fmean function in Python's statistics module calculates the arithmetic mean (average) of a given set of numbers using floating-point arithmetic. This function is particularly useful for maintaining precision in calculations with floating-point numbers.

Table of Contents

1. Introduction
2. statistics.fmean Function Syntax
3. Examples
   • Basic Usage
   • Mean of a List of Numbers
   • Mean of a Tuple of Numbers
   • Handling Different Types of Numeric Data
4. Real-World Use Case
5. Conclusion

Introduction

The statistics.fmean function is part of the statistics module, which provides functions for mathematical statistics of numeric data. The arithmetic mean is the sum of the data divided by the number of data points. Using floating-point arithmetic helps maintain precision, especially with large datasets or data with many decimal places.

statistics.fmean Function Syntax

Here's how you use the statistics.fmean function:

import statistics

mean_value = statistics.fmean(data)

Parameters:

• data: A sequence or iterable of numeric data (list, tuple, etc.).

Returns:

• The arithmetic mean of the given data as a floating-point number.

Raises:

• StatisticsError: If data is empty.

Examples

Basic Usage

Calculate the mean of a list of numbers.

import statistics

data = [1, 2, 3, 4, 5]
mean_value = statistics.fmean(data)
print(f"Mean: {mean_value}")

Output:

Mean: 3.0

Mean of a List of Numbers

Calculate the mean of a list of integers.

import statistics

numbers = [10, 20, 30, 40, 50]
mean_value = statistics.fmean(numbers)
print(f"Mean of numbers: {mean_value}")

Output:

Mean of numbers: 30.0

Mean of a Tuple of Numbers

Calculate the mean of a tuple of floats.

import statistics

numbers = (1.5, 2.5, 3.5, 4.5, 5.5)
mean_value = statistics.fmean(numbers)
print(f"Mean of numbers: {mean_value}")

Output:

Mean of numbers: 3.5

Handling Different Types of Numeric Data

Calculate the mean of a mixed list of integers and floats.

import statistics

numbers = [1, 2.5, 3, 4.5, 5]
mean_value = statistics.fmean(numbers)
print(f"Mean of numbers: {mean_value}")

Output:

Mean of numbers: 3.2

Real-World Use Case

Calculating Average Temperature

Calculate the average temperature from a list of daily temperatures using floating-point arithmetic.

import statistics

temperatures = [22.5, 23.0, 21.5, 20.0, 22.0, 21.0, 23.5]
average_temperature = statistics.fmean(temperatures)
print(f"Average temperature: {average_temperature}")

Output:

Average temperature: 21.928571428571427

Conclusion

The statistics.fmean function is a simple and effective way to calculate the arithmetic mean of a set of numbers in Python using floating-point arithmetic. It is particularly useful for maintaining precision in calculations with large datasets or data with many decimal places. This function makes it easy to determine the mean, which is a common requirement in various fields such as science, finance, and engineering.