How can I force division to be floating point? Division keeps rounding down to 0?

When integers take the floor

With Python 2, when using integers on both sides of the division operator, we inherently get an integer result, an operation known as floor division. Rather funnily, it resembles Lucy holding the football for Charlie Brown — simply falling short of expectations.

To force a float result in Python 2, you can cast one operand to float. Alternatively, you can align Python 2's behavior with Python 3 by using:

from __future__ import division
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Adding this import at the beginning of your script ensures floating-point division throughout.

Enacting floating point division

Beyond simply casting to float, a neat trick is to multiply one operand by 1.0. This implicit conversion to a floating point number ensures floating-point division:

c = a / (b * 1.0)
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Although brief, this approach may not be as understandable to greenhorn programmers compared to casting.

Running a gauntlet of edge cases

Take your numbers for a spin and ensure you've got the right driver behind the division wheel:

# Zero and negative numbers
print(-5.0 / 2)   # Outputs: -2.5
print(5.0 / -2)   # Outputs: -2.5
print(5.0 / 0)    # Raises ZeroDivisionError. Physics still applies in Python, you can't divide by zero
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Exception handling is your co-driver in this journey. It helps you tackle incidentals like ZeroDivisionError:

try:
    result = a / float(b)
except ZeroDivisionError:
    result = float('inf')  # Better infinite than sorry 
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And do remember, while integers and floats make a lovely pair, involving complex numbers in the mix can lead to TypeError in Python 2.

Python's great divide: the 2 to 3 transition

Python 2 rode into the sunset, leaving Python 3 holding the reins. However, if you're stuck in the past, -Qnew is your time machine to bring Python 2's division behavior to Python 3's standard.

python -Qnew script.py
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Remember, while -Qnew brings you to the future, it may cause turbulence with modules expecting Python 2-style division.

And even while time traveling, it's good to leave a reminder for yourself:

from __future__ import division
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In the brave new world of Python 3.x, integer division (floor division) isn't forgotten, you can still use the // operator.

Coding lore: document for future seers

Python it may be, but it's not the snake - it won't bite. Add comments about your division methodology for easier understanding, especially for the code maintainers of the future. Because no one wants to play detective within a fortress of code.