Why Does Integer Division in Python 2 Give Unexpected Results with Negative Numbers?

Unexpected Outcomes of Integer Division

In Python 2, performing integer division with negative numbers can yield surprising results. For instance, when dividing 8 by -7, the result is -2, despite the expected quotient being around -1.143.

Understanding Floor Division

Integer division, often referred to as "floor division" in Python 2, rounds the result down towards the nearest integer. This behavior dictates that even when dividing positive and negative integers, the output is always more negative.

Example Conundrums

This rounding down principle leads to perplexing results, as illustrated by the following division operations:

• 8/(-7) = -2
• 8/7 = 1

Python 3 Fixes the Anomaly

In Python 3, this issue is resolved. For the same operation, 8/(-7), the output is -1.143. However, if the desired behavior is integer division, using the "//" operator will replicate the result from Python 2.

Technical Explanation

In Python 2, the type of an integer divided by another integer is also an integer. Hence, the result is rounded down to the nearest integer. Python 3 introduces automatic type conversion, which allows for the result to be represented as a floating-point number, retaining its actual value.

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