介绍
For arbitrary precision mathematics PHP offers the Binary Calculator which
supports numbers of any size and precision, represented as strings.
需求
Since PHP 4.0.4, libbcmath is bundled with PHP. You don't need any
external libraries for this extension.
安装
In PHP 4, these functions are only available if PHP was
configured with --enable-bcmath.
In PHP 3, these functions are only available if PHP was
NOT configured with --disable-bcmath.
PHP 的 Windows 版本已经内置该扩展模块的支持。您无需加载任何附加的扩展库即可使用这些函数。
运行时配置
这些函数的行为受到全局配置文件 php.ini 的影响。
表格 1. BC math configuration options
| Name | Default | Changeable |
|---|
| bcmath.scale | 0 | PHP_INI_ALL |
For further details and definition of the PHP_INI_* constants see
ini_set().
以下是该配置选项的简要解释。
- bcmath.scale
integer
Number of decimal digits for all bcmath functions. See also
bcscale().
