📐 PHP Math Magic: Understanding floor(), ceil(), and round()
When working with numbers in PHP, rounding becomes essential—whether you’re paginating results or packing boxes. PHP gives us three handy functions for rounding:
1️⃣ floor() – Rounding Down
- What it does: Always rounds a number down to the nearest whole number.
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Example:
$number = 3.7; $floored = floor($number); // 3 - When to use it: When you must not exceed a value—e.g., full pages in a document.
2️⃣ ceil() – Rounding Up
- What it does: Always rounds a number up to the nearest whole number.
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Example:
$number = 3.2; $ceiled = ceil($number); // 4 - When to use it: When you must not fall short—e.g., counting how many boxes you need to pack items.
3️⃣ round() – Nearest Value Rounding
- What it does: Rounds to the nearest integer (or decimal precision).
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How it works:
- If decimal ≥ 0.5 → rounds up
- If decimal < 0.5 → rounds down
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Examples:
round(3.7); // 4 round(3.2); // 3 round(3.14159, 2); // 3.14 - When to use it: For general-purpose rounding.
🔎 Summary
- ✅ Use
floor()to always round down - ✅ Use
ceil()to always round up - ✅ Use
round()to round to the nearest value
🧠 QUIZ
Question 1: You need to calculate how many boxes are required to pack items, ensuring you don’t run short. 👉 Which PHP function is best and why?
Question 2: What is the output of the following PHP code?
$number = 4.3;
$result = round($number, 0);
echo $result;
💬 Comment your answers below!
