【C语言取整函数的总结】
在头文件<math.h>下,四舍五入、向上取整、向下取整。详见文档。
四舍五入: double round(double arg);//返回与arg最接近的整数
向上取整: double ceil(double arg);//返回不小于arg的最小整数
向下取整: double floor(double arg);//返回不大于arg的最大整数
示例:
#include <stdio.h> #include <math.h>//round(),floor(),ceil() int main() { //四舍五入 printf("round(+2.33) = %+.1f ",round(2.33)); printf("round(+2.49) = %+.1f ",round(2.49)); printf("round(+2.5) = %+.1f ",round(2.5)); printf("round(+2.67) = %+.1f\n",round(2.67)); printf("round(-2.33) = %+.1f ",round(-2.33)); printf("round(-2.49) = %+.1f ",round(-2.49)); printf("round(-2.5) = %+.1f ",round(-2.5)); printf("round(-2.67) = %+.1f\n",round(-2.67)); //向下取整 printf("floor(+2.7) = %+.1f ", floor(2.7)); printf("floor(-2.7) = %+.1f ", floor(-2.7)); printf("floor(-0.0) = %+.1f\n", floor(-0.0)); //向上取整 printf("ceil(+2.4) = %+.1f ", ceil(2.4)); printf("ceil(-2.4) = %+.1f ", ceil(-2.4)); printf("ceil(-0.0) = %+.1f\n", ceil(-0.0)); return 0; }
输出:
round(+2.33) = +2.0 round(+2.49) = +2.0 round(+2.5) = +3.0 round(+2.67) = +3.0 round(-2.33) = -2.0 round(-2.49) = -2.0 round(-2.5) = -3.0 round(-2.67) = -3.0 floor(+2.7) = +2.0 floor(-2.7) = -3.0 floor(-0.0) = -0.0 ceil(+2.4) = +3.0 ceil(-2.4) = -2.0 ceil(-0.0) = -0.0