Objective-C适用C数学函数

常用函数：

1、指数运算

NSLog(@"%.f", pow(3,2) ); //result 9

NSLog(@"%.f", pow(3,3) ); //result 27

2、开平方运算

NSLog(@"%.f", sqrt(16) ); //result 4

NSLog(@"%.f", sqrt(81) ); //result 9

3、上舍入

NSLog(@"res: %.f", ceil(3.000000000001)); //result 4

NSLog(@"res: %.f", ceil(3.00)); //result 3

4、下舍入

NSLog(@"res: %.f", floor(3.000000000001)); //result 3

NSLog(@"res: %.f", floor(3.9999999)); //result 3

5、四舍五入

NSLog(@"res: %.f", round(3.5)); //result 4

NSLog(@"res: %.f", round(3.46)); //result 3

NSLog(@"res: %.f", round(-3.5)); //return -4

6、最小值

NSLog(@"res: %.f", fmin(5,10)); //result 5

7、最大值

NSLog(@"res: %.f", fmax(5,10)); //result 10

8、绝对值

NSLog(@"res: %.f", fabs(10)); //result 10

NSLog(@"res: %.f", fabs(-10)); //result 10