PHP Math Functions

In this page:

Basic Rounding Functions
Minimum and Maximum Values
Random Number Generation
Absolute and Power Calculations
Mathematical Conversions

Basic Rounding Functions

round(), ceil(), and floor() all turn a float into a whole number but disagree on direction: round() picks the nearest integer, ceil() always rounds up, and floor() always rounds down, which matters for things like billing calculations.

Example: Basic Rounding Functions

php

<?php
echo round(4.5) . "\n";
echo ceil(4.1) . "\n";
echo floor(4.9);
?>

Minimum and Maximum Values

min() and max() accept either a list of separate arguments or a single array, returning the smallest or largest value found -- handy for clamping a value into an allowed range.

Example: Minimum and Maximum Values

php

<?php
echo min(3, 1, 4) . "\n";
echo max([3, 1, 4]);
?>

Random Number Generation

rand() is fine for non-critical randomness like shuffling a quiz, but random_int() uses a cryptographically secure source and should be preferred anywhere randomness affects security, like generating a token.

Example: Random Number Generation

php

<?php
echo rand(1, 10) . "\n";
echo random_int(1, 10);
?>

Absolute and Power Calculations

abs() strips a number's sign, sqrt() computes a square root, and pow() raises a base to a given exponent -- together covering the calculations that show up constantly in geometry and finance code.

Example: Absolute and Power Calculations

php

<?php
echo abs(-5) . "\n";
echo sqrt(16) . "\n";
echo pow(2, 3);
?>

Mathematical Conversions

base_convert() converts a number between arbitrary numeric bases (like hex to binary), which is useful when working with color codes, bitmasks, or other data that's naturally expressed in a non-decimal base.

Example: Mathematical Conversions

php

<?php
echo base_convert("FF", 16, 2);
?>

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