Sophie: php-manual-zh-5.2.4-1mdv2008.1 noarch

php-manual-zh-5.2.4-1mdv2008.1.noarch.rpm

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<HTML
><HEAD
><TITLE
>pi</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK
REL="HOME"
TITLE="PHP 手册"
HREF="index.html"><LINK
REL="UP"
TITLE="Math 数学函数"
HREF="ref.math.html"><LINK
REL="PREVIOUS"
TITLE="octdec"
HREF="function.octdec.html"><LINK
REL="NEXT"
TITLE="pow"
HREF="function.pow.html"><META
HTTP-EQUIV="Content-type"
CONTENT="text/html; charset=UTF-8"></HEAD
><BODY
CLASS="refentry"
BGCOLOR="#FFFFFF"
TEXT="#000000"
LINK="#0000FF"
VLINK="#840084"
ALINK="#0000FF"
><DIV
CLASS="NAVHEADER"
><TABLE
SUMMARY="Header navigation table"
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TH
COLSPAN="3"
ALIGN="center"
>PHP 手册</TH
></TR
><TR
><TD
WIDTH="10%"
ALIGN="left"
VALIGN="bottom"
><A
HREF="function.octdec.html"
ACCESSKEY="P"
>上一页</A
></TD
><TD
WIDTH="80%"
ALIGN="center"
VALIGN="bottom"
></TD
><TD
WIDTH="10%"
ALIGN="right"
VALIGN="bottom"
><A
HREF="function.pow.html"
ACCESSKEY="N"
>下一页</A
></TD
></TR
></TABLE
><HR
ALIGN="LEFT"
WIDTH="100%"></DIV
><H1
><A
NAME="function.pi"
></A
>pi</H1
><DIV
CLASS="refnamediv"
><A
NAME="AEN108929"
></A
><P
>    (PHP 3, PHP 4, PHP 5)</P
>pi&nbsp;--&nbsp;得到圆周率值</DIV
><DIV
CLASS="refsect1"
><A
NAME="AEN108932"
></A
><H2
>说明</H2
>float <B
CLASS="methodname"
>pi</B
> ( void  )<BR
></BR
><P
>&#13;     返回圆周率的近似值。返回值的 <A
HREF="language.types.float.html"
><B
CLASS="type"
>float</B
></A
>
     精度是由 <TT
CLASS="filename"
>php.ini</TT
> 中的 <A
HREF="ini.core.html#ini.precision"
>precision</A
>
     指令确定。默认值是 <TT
CLASS="literal"
>14</TT
>。你也可以使用
     <TT
CLASS="constant"
><B
>M_PI</B
></TT
> 常量，该常量产生与 <B
CLASS="function"
>pi()</B
> 完全相同的结果。
    </P
><P
>&#13;      <TABLE
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
CLASS="EXAMPLE"
><TR
><TD
><DIV
CLASS="example"
><A
NAME="AEN108946"
></A
><P
><B
>例 1. <B
CLASS="function"
>pi()</B
></B
></P
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
CELLPADDING="5"
><TR
><TD
><code><font color="#000000">
<font color="#0000BB">&lt;?php<br /></font><font color="#007700">echo </font><font color="#0000BB">pi</font><font color="#007700">(); </font><font color="#FF8000">// 3.1415926535898<br /></font><font color="#007700">echo </font><font color="#0000BB">M_PI</font><font color="#007700">; </font><font color="#FF8000">// 3.1415926535898<br /></font><font color="#0000BB">?&gt;</font>
</font>
</code></TD
></TR
></TABLE
></DIV
></TD
></TR
></TABLE
>
   </P
></DIV
><DIV
CLASS="NAVFOOTER"
><HR
ALIGN="LEFT"
WIDTH="100%"><TABLE
SUMMARY="Footer navigation table"
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
><A
HREF="function.octdec.html"
ACCESSKEY="P"
>上一页</A
></TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="index.html"
ACCESSKEY="H"
>起始页</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
><A
HREF="function.pow.html"
ACCESSKEY="N"
>下一页</A
></TD
></TR
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
>octdec</TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="ref.math.html"
ACCESSKEY="U"
>上一级</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
>pow</TD
></TR
></TABLE
></DIV
></BODY
></HTML
>