Absolute values in Python

The Python abs() function returns the absolute value of a number. It works with integers, floating-point numbers, and complex numbers. Here are several examples to illustrate its usage:

The abs() function can be used to find the absolute value of positive and negative integers.

In this code, we apply abs() to both a positive and negative integer. For the positive number, the function returns the same value, while for the negative number, it returns its positive counterpart.

The output will be:

The abs() function also works with floating-point numbers, maintaining their decimal precision.

This example demonstrates that abs() preserves the decimal places of floating-point numbers while returning their absolute values.

The output will be:

For complex numbers, abs() returns the magnitude of the number, calculated using the Pythagorean theorem.

In this case, abs() calculates the magnitude of the complex number using the formula √(a² + b²), where a is the real part and b is the imaginary part.

The output will be:

The abs() function can be useful in various calculations, such as finding the difference between two numbers regardless of their order.

This example shows how abs() can be used to find the absolute difference between two numbers, which is useful when you're interested in the magnitude of the difference rather than which number is larger.

In Python, binary numbers are prefixed with '0b'. The abs() function works directly with these binary literals.

In this example, we're using the '0b' prefix to denote binary literals. Python interprets these as integers, so we can apply abs() directly without any conversion.

The output will be:

For octal numbers, we use the '0o' prefix to denote an octal literal in Python.

This code demonstrates using abs() with an octal number. Python automatically converts the octal to decimal before applying abs().

The output is:

Hexadecimal numbers in Python are prefixed with '0x'.

Here, we take the absolute value of a negative hexadecimal number. Python converts it to decimal internally before applying abs().

These examples demonstrate that regardless of the base in which a number is represented, Python's abs() function always operates on the decimal (base 10) equivalent of the number. For non-decimal bases, Python first converts the number to its decimal representation before applying the abs() function.

In addition to the abs() function, there is a function called fabs(). They are both used to calculate absolute values, but they have some key differences.

abs() is a built-in Python function, so it doesn't require importing any module. It works with integers, floating-point numbers, and complex numbers, as we have seen above.

fabs() on the other hand is part of the math module, so you need to import it using “from math import fabs”. It only works with real numbers (integers and floats), not complex numbers. Further,this function always returns a float, even if the input is an integer.

In most cases, abs() is more versatile and commonly used. However, if you're working exclusively with real numbers and need the best performance, math.fabs() might be preferable.

Thus the abs() function in Python is a very effective one, handling different numeric types and providing a simple way to obtain absolute values or magnitudes in various scenarios.

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Example 1: Absolute Value of Integers

Example 2: Absolute Value of Floating-Point Numbers

Example 3: Absolute Value of Complex Numbers

​​Example 4: Using abs() in Calculations

Example 5: Using abs() with binary (base 2) numbers

Example 6: Using abs() with octal (base 8) numbers

Example 6: Using abs() with hexadecimal (base 12) numbers

abs() vs fabs() in Python