albertoarena/calculator

Simple calculator

0.2 2016-04-23 09:58 UTC

Requires

• php: >=5.3.0
• crysalead/kahlan: ^2.4

MIT

• Alberto Arena

README

Simple PHP calculator, inspired by shunting-yard algorithm.

Support of basic operators (+, -, /, *, ^), trigonometric operators and precedence.

Operators

The Order of operators follows the standard (see Wikipedia):

High precedence

• ^: exponent (power)
• √: square root (alias sqrt)

Medium precedence

• \*: multiplication
• /: division
• sin: sine
• cos: cosine
• tan: tangent
• asin: arc sine
• acos: arc cosine
• atan: arc tangent

Low precedence

• +: addition
• -: subtraction

How to use it

A working example is available in samples/basic.php.

use Calculator\Calculator;

$calculator = new Calculator();

// Basic operators
$calculator->number(1)
    ->operator('+')->number(5)
    ->operator('*')->number(3.5)
    ->operator('/')->number(2)
    ->execute();

echo $calculator;
// ==> 1 + 5 * 3.5 / 2 = 9.75

// Power
$calculator->number(2)
    ->operator('*')->number(2)
    ->operator('^')->number(4)
    ->execute();

echo $calculator;
// ==> 2 * 2 ^ 4 = 32

// Square root
$result = $calculator->number(9)
    ->operator('√')
    ->execute();

echo $calculator;
// ==> √ 9 = 3

// Trigonometry
$result = $calculator->number(1)
    ->operator('cos')
    ->execute();

echo $calculator;
// ==> cos (1) = 0.54030230586814