PowerShell:
Rounding numbers

How to:

You’ve got a few handy cmdlets and methods in PowerShell for rounding:

• Round() method from Math class

[Math]::Round(15.68) # Rounds to 16

• Specify decimals:

[Math]::Round(15.684, 2) # Rounds to 15.68

• Ceiling() and Floor(), for always rounding up or down:

[Math]::Ceiling(15.2) # Rounds up to 16
[Math]::Floor(15.9) # Rounds down to 15

Deep Dive

Rounding numbers is no newcomer; it’s been around since ancient times, useful for trade, science, and timekeeping. Talking about PowerShell, [Math]::Round() follows “Banker’s Rounding” by default, where 0.5s goes to the nearest even number, reducing bias in statistical operations.

You’re not just stuck with [Math] methods though. Want more control? Check out [System.Math]::Round(Number, Digits, MidpointRounding) where you can set how midpoints are handled: away from zero or to even (aka Banker’s Rounding).

Another angle: the System.Globalization.CultureInfo object. It helps with locale-specific formatting and rounding preferences when dealing with international numbers.

See Also

• Microsoft’s official docs on Math methods: Link
• Decimal rounding specifics in .NET: Link
• Discussions on rounding in StackOverflow: Link