C#:
Rounding numbers
How to:
Here’s the round-trip ticket for rounding numbers in C#:
using System;
public class RoundingExamples
{
public static void Main()
{
double originalNumber = 123.4567;
// Round to nearest whole number
double rounded = Math.Round(originalNumber);
Console.WriteLine(rounded); // Output: 123
// Specify number of decimal places
double roundedTwoDecimalPlaces = Math.Round(originalNumber, 2);
Console.WriteLine(roundedTwoDecimalPlaces); // Output: 123.46
// Round up regardless of the next digit
double roundedUp = Math.Ceiling(originalNumber);
Console.WriteLine(roundedUp); // Output: 124
// Round down regardless of the next digit
double roundedDown = Math.Floor(originalNumber);
Console.WriteLine(roundedDown); // Output: 123
}
}
Deep Dive
Back in the day, rounding was a no-brainer for trimming computational costs. Every cycle counted, and trimming numbers saved precious time. Fast-forward to modern C#, and it’s about managing doubles and decimals’ notorious predisposition to precision errors and display quirks.
Beyond Math.Round
, Math.Floor
, and Math.Ceiling
, the MidpointRounding
enum lets us dictate the fate of poor, middle-sitting digits—it’s the crossroads between banking rules and the playground fairness of “round half up”.
For tougher crowds, like serious math or finance applications, we’ve got decimal
over double
, cutting down on rounding drama by offering higher precision—less rounding, less problems.