计算时中常用到一些函数, 整理一下
<algorithm>
?️ 最大最小 max min
//可以输入int char double等
std::cout << "max(2,1)==" << std::max(2,1) << '\n';
std::cout << "max('a','z')==" << std::max('a','z') << '\n';
std::cout << "max(3.14,2.73)==" << std::max(3.14,2.73) << '\n';
?️ 更多
<cmath>
?️ 绝对值 abs
int i_c = abs(-29); //i_c = 29
?️ 向下/向上取整 cell
printf ( "ceil of 2.3 is %.1f\n", ceil(2.3) );//3
printf ( "floor of 3.8 is %.1lf\n", floor (-4.8) );//-4
?️ 开方 pow
printf ("7 ^ 3 = %f\n", pow (7.0, 3.0) );
?️ 开根号(1/2) sqrt
double param, result;
param = 1024.0;
result = sqrt (param);
printf ("sqrt(%f) = %f\n", param, result );
?️取对数 log(e为底) , log10(10为底)
double param, result;
param = 5.5;
result = log (param);
printf ("log(%f) = %f\n", param, result );
?️ 正弦 sin (用的弧度)
#define PI 3.14159265
double result;
result = sin (30*PI/180); //sin(π/6) = 1/2
?️ arccos acos(传double,返回double)
#define PI 3.14159265
double param, result;
param = 0.5;
result = acos (param) * 180.0 / PI;
printf ("The arc cosine of %f is %f degrees.\n", param, result);
其他
?️ 无穷大和无穷小
double max = DBL_MAX;
double min = DBL_MIN;