PHP code example of rizalmf / deductive-formula

1. Go to this page and download the library: Download rizalmf/deductive-formula library. Choose the download type require.

2. Extract the ZIP file and open the index.php.

3. Add this code to the index.php.
    
        
<?php
require_once('vendor/autoload.php');

/* Start to develop here. Best regards https://php-download.com/ */

    

rizalmf / deductive-formula example snippets



use rizalmf\formula\DeductiveFormula;
use rizalmf\formula\exception\FormulaException;


try {
    $expression = '{foo}^({bar}/2+(2+3^(1/2)))';
    $requestedVariables = $formula->setFormula($expression);
    var_dump($formula->getFormula());
    var_dump($requestedVariables);

} catch (FormulaException $e) {
    // handle Exceptions
}

// output : 
// {foo}^({bar}/2+(2+3^(1/2)))
// array ([0] => "foo", [1] => "bar")

    // ...

    // 1. define value per variable
    $formula->setVariable("foo", 4);
    $formula->setVariable("bar", 1);

    // 2. use array
    $formula->setVariables([
        "foo" => 4,
        "bar" => 1
    ]);

    // ...

    // 1. get value from specific variable
    var_dump($formula->getVariable("foo"));
    // output : 4

    // 2. get values all variables
    var_dump($formula->getVariables());
    // output : array ([foo] => 4, [bar] => 1)

    // 1. get possible variables from Formula
    var_dump($formula->getRequestedVariables());
    // output : array ([0] => "foo", [1] => "bar")


    $result = $formula->execute();
    var_dump($result);

    // output : 353.141268350837

    // (optional) set limit iteration calculating machine. default 200
    $formula->setLimit(50);

    // show prepared formula
    var_dump($formula->getFormulaExposed());
    // output : 4^(1/2+(2+3^(1/2)))

    // debug
    $result = $formula->execute(true);
    var_dump($result);
    // output : 
    // iteration-1 => 4^(1/2+(2+3^(1/2)))
    // iteration-2 => 4^(1/2+(2+3^0.50))
    // iteration-3 => 4^(1/2+(2+1.73205080756888))
    // iteration-4 => 4^(1/2+3.73205080756888)
    // iteration-5 => 4^(0.50+3.73205080756888)
    // iteration-6 => 4^4.23205080756888
    // 353.141268350837

    FormulaException
        |- BadFormulaException