在线手册：中文英文

deg2rad

(PHP 4, PHP 5)

deg2rad — 将角度转换为弧度

float deg2rad ( float $number )

本函数把 number 从角度转换成弧度。

Example #1 deg2rad()


<?php
    
    echo deg2rad(45); // 0.785398163397
    var_dump(deg2rad(45) === M_PI_4); // bool(true)
    
    ?>

参见 rad2deg()。

在线手册：中文英文

PHP手册 - N: 将角度转换为弧度

christian dot ubu at NOSPAMHERE dot gmail dot com (13-Mar-2009 03:18)

Never use deg2rad() in loops, use $rad = ($deg * M_PI / 180) instead which is faster!

john dot navratil at sbcglobal dot net (11-Feb-2007 03:32)

This does a simple scaling with the results that deg2rad(720) is 4PI. For navigation purposes you may wish to mod the results with 2PI.