C++三角函數、指對數、冪次開方、小數進位、切除小數、絕對值
一開始,他們標頭檔都要加#include<cmath>
- 三角函數
- 用法:
- double sin ( double 徑度 )
- double cos ( double 徑度 )
- double tan ( double 徑度 )
- #include<iostream>
- #include<cstdlib>
- #include<cmath>
- using namespace std;
- #define PI 3.14159 //定義PI=3.14159
- int main()
- {
- double a = sin(30*(PI/180));
- cout << "sin30 = "<<a <<endl;
- double c = cos(30*(PI/180));
- cout << "cos30 = "<<c <<endl;
- double t = tan(30*(PI/180));
- cout << "tan30 = "<<t <<endl;
- }
2.指數和對數
- double exp( 數值 ) //以e為底的數值次方
- double log( 數值 ) // 傳回ln數值(或稱log以e為底數的數值)
- double log10( 數值 )
int main()
{
double a = log(2);
double b = log10(2);
double c = exp(2);
cout << a << endl;
cout << b << endl;
cout << c << endl;
}
3.冪次和開方
- double pow ( 底數, 冪次 )
- double sqrt ( 數值 )
int main()
{
double a = pow(2,3); //2的3次方
double b = sqrt(3); // 根號3
cout << a << endl;
cout << b << endl;
}
4.小數進位和切除小數
- double ceil ( 數值 ) //若有小數( 0.10.9 )則進位
- double floor ( 數值 ) //若有小數( 0.10.9 )則刪除
- 正負數要注意,結果會相反
int main()
{
int c1 = ceil(3.33);
int f1 = floor(3.33);
int c2 = ceil(-3.33);
int f2 = floor(-3.33);
cout << c1 << endl;
cout << f1 << endl;
cout << c2 << endl;
cout << f2 << endl;
}
5.絕對值
- double fabs ( 數值 )
int main()
{
int a = fabs(2);
int b = fabs(-2);
cout << a << endl;
cout << b << endl;
}
文章標籤
全站熱搜
創作者介紹
