<html><head><title>JavaScript Math atan()方法</title></head><body><scripttype="text/javascript">var value =Math.atan(-1);
document.write("第一个测试值 : "+ value );var value =Math.atan(.5);
document.write("<br/>第二个测试值 : "+ value );
value =Math.atan(30);
document.write("<br/>第三个测试值 : "+ value );var value =Math.atan("string");
document.write("<br/>第四个测试值 : "+ value );</script></body></html>