PHP 8.1.0 RC 4 available for testing


(PHP 4, PHP 5, PHP 7)

bcsubSubtract one arbitrary precision number from another


bcsub ( string $num1 , string $num2 , int|null $scale = null ) : string

Subtracts the num2 from the num1.



The left operand, as a string.


The right operand, as a string.


Acest parametru opțional este utilizat pentru a stabili numărul cifrelor după virgulă din rezultat. Dacă este omis, valoarea implicită va fi cea stabilită global cu funcția bcscale(), sau va fi 0 dacă nu a fost stabilită cu ajutorul acestei funcții.

Valorile întoarse

The result of the subtraction, as a string.

Istoricul schimbărilor

Versiune Descriere
8.0.0 scale is now nullable.


Example #1 bcsub() example


$b '5';

bcsub($a$b);     // -3
echo bcsub($a$b4);  // -3.7660


A se vedea și

  • bcadd() - Add two arbitrary precision numbers

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User Contributed Notes 2 notes

nd at snackbox dot org
3 years ago
The parameter order here is probably fairly obvious to most people (subtract right from left), but to clarify with a simple use case since I was struggling with this at the end of a long day:

echo bcsub('7', '5'); // 7 - 5 = '2'
echo bcsub('12', '17'); // 12 - 17 = '-5'

Provide the parameters in the same order you would when using a normal subtraction operator.
charles dot adrian dot wood at gmail dot com
2 years ago
Please note that bcsub will fail in non-obvious ways if it's fed something that cannot be converted to a number. For instance:

bcsub('yes', 'no') === '0'

Yes, if you put garbage in, you get garbage out. Just don't expect bcsub to throw an error when you feed it an entirely non-numeric value.
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