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bcsub

(PHP 4, PHP 5, PHP 7)

bcsub2个任意精度数字的减法

说明

string bcsub ( string $left_operand , string $right_operand [, int $scale = int ] )

左操作数减去右操作数.

参数

left_operand

字符串类型的左操作数.

right_operand

字符串类型的右操作数.

scale

此可选参数用于设置结果中小数点后的小数位数。也可通过使用 bcscale() 来设置全局默认的小数位数,用于所有函数。

返回值

返回减法之后结果为字符串类型.

范例

Example #1 bcsub() example

<?php

$a 
'1.234';
$b '5';

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

?>

参见

  • bcadd() - 2个任意精度数字的加法计算

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User Contributed Notes 1 note

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nd at snackbox dot org
8 months 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:

<?php
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.
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