主题:[讨论]请大家帮忙看一个小问题
//下面是java Math类的一个小练习,为什么不进行乘除100的操作,得到的结果就不正确呢?请求大家指点一下,谢谢!
//right,这个结果正确
public class SinCosTan {
public static void main(String[] args) {
double sin30,cos60,tan45;
sin30 = Math.round(Math.sin(Math.toRadians(30))*100);
cos60 = Math.round(Math.cos(Math.PI/3)*100);
tan45 = Math.round(Math.tan(Math.PI/4)*100);
System.out.println("sin30="+sin30/100);
System.out.println("cos60="+cos60/100);
System.out.println("tan45="+tan45/100);
}
}
//wrong,这个结果有问题
public class SinCosTan {
public static void main(String[] args) {
double sin30,cos60,tan45;
sin30 = Math.sin(Math.toRadians(30));
cos60 = Math.cos(Math.PI/3);
tan45 = Math.tan(Math.PI/4);
System.out.println("sin30="+sin30);
System.out.println("cos60="+cos60);
System.out.println("tan45="+tan45);
}
}
//right,这个结果正确
public class SinCosTan {
public static void main(String[] args) {
double sin30,cos60,tan45;
sin30 = Math.round(Math.sin(Math.toRadians(30))*100);
cos60 = Math.round(Math.cos(Math.PI/3)*100);
tan45 = Math.round(Math.tan(Math.PI/4)*100);
System.out.println("sin30="+sin30/100);
System.out.println("cos60="+cos60/100);
System.out.println("tan45="+tan45/100);
}
}
//wrong,这个结果有问题
public class SinCosTan {
public static void main(String[] args) {
double sin30,cos60,tan45;
sin30 = Math.sin(Math.toRadians(30));
cos60 = Math.cos(Math.PI/3);
tan45 = Math.tan(Math.PI/4);
System.out.println("sin30="+sin30);
System.out.println("cos60="+cos60);
System.out.println("tan45="+tan45);
}
}