Detailed explanation of trigonometric functions in C++

Detailed explanation of trigonometric functions in C

Trigonometric functions are one of the basic functions in mathematics and are also widely used in computer programming. C is a powerful programming language that provides a range of functions and libraries for computing trigonometric functions. This article will introduce the trigonometric functions in C in detail, including the usage and precautions of sin, cos, tan, asin, acos, atan and other functions.

1. sin function: The sin function is used to calculate the sine value of an angle. Its prototype is as follows:

   double sin(double angle);

   where angle represents the angle value to be calculated, and the return value is calculated sine value. It should be noted that the parameters accepted by trigonometric functions in C are in radians. If the angle system is used, the angles need to be converted into radians. For example, to calculate the sine of an angle of 30 degrees, you can use the following code:

   #include <cmath>
   #include <iostream>
   using namespace std;
   
   int main() {
    double angle = 30.0;
    double radian = angle * M_PI / 180.0;
    double result = sin(radian);
    cout << "sin(30) = " << result << endl;
    return 0;
   }

   The running result is: sin(30) = 0.5

2. cos function: The cos function is used Calculate the cosine value of an angle, its prototype is as follows:

   double cos(double angle);

   where angle represents the angle value to be calculated, and the return value is the calculated cosine value. Likewise, the cos function in C also accepts arguments in radians. For example, to calculate the cosine of a 60-degree angle, you can use the following code:

   #include <cmath>
   #include <iostream>
   using namespace std;
   
   int main() {
    double angle = 60.0;
    double radian = angle * M_PI / 180.0;
    double result = cos(radian);
    cout << "cos(60) = " << result << endl;
    return 0;
   }

   The running result is: cos(60) = 0.5

3. tan function: The tan function is used Calculate the tangent value of an angle, its prototype is as follows:

   double tan(double angle);

   where angle represents the angle value to be calculated, and the return value is the calculated tangent value. Likewise, the tan function in C also accepts arguments in radians. For example, to calculate the tangent of a 45-degree angle, you can use the following code:

   #include <cmath>
   #include <iostream>
   using namespace std;
   
   int main() {
    double angle = 45.0;
    double radian = angle * M_PI / 180.0;
    double result = tan(radian);
    cout << "tan(45) = " << result << endl;
    return 0;
   }

   The running result is: tan(45) = 1

4. asin function: asin function is used Calculate the arcsine value of a value (in radians). Its prototype is as follows:

   double asin(double value);

   where value represents the value to be calculated as the arcsine value, and the return value is the calculated arcsine value in radians. It should be noted that the return value range of the asin function is [-pi/2, pi/2]. When the input value exceeds the value range, the return value will overflow. For example, to calculate the arcsine of 0.5, you can use the following code:

   #include <cmath>
   #include <iostream>
   using namespace std;
   
   int main() {
    double value = 0.5;
    double result = asin(value);
    cout << "asin(0.5) = " << result << endl;
    return 0;
   }

   The running result is: asin(0.5) = 0.523599

5. acos function: The acos function is used for calculation The inverse cosine of a value (in radians), its prototype is as follows:

   double acos(double value);

   where value represents the value to be calculated as the inverse cosine, and the return value is the calculated inverse cosine in radians. Similar to the asin function, the return value range of the acos function is [0, pi]. For example, to calculate the arc cosine of 0.5, you can use the following code:

   #include <cmath>
   #include <iostream>
   using namespace std;
   
   int main() {
    double value = 0.5;
    double result = acos(value);
    cout << "acos(0.5) = " << result << endl;
    return 0;
   }

   The running result is: acos(0.5) = 1.0472

6. atan function: the atan function is used for calculation The arctangent value of a value (in radians), its prototype is as follows:

   double atan(double value);

   where value represents the value to calculate the arctangent value, and the return value is the calculated arctangent value in radians. The return value range of the atan function is [-pi/2, pi/2]. For example, to calculate the arc tangent of 1, you can use the following code:

   #include <cmath>
   #include <iostream>
   using namespace std;
   
   int main() {
    double value = 1.0;
    double result = atan(value);
    cout << "atan(1) = " << result << endl;
    return 0;
   }

   The running result is: atan(1) = 0.785398

In addition to the functions introduced above, C Some other trigonometric functions are also provided, such as sinh, cosh, tanh, asinh, acosh, and atanh. The usage and precautions of these functions are similar to the functions introduced above.

When using trigonometric functions in C, you need to include the cmath header file and link the corresponding math library when compiling (if you use the g compiler, you can add the -lm option). In addition, you also need to pay attention to handling special situations, such as inputting values ​​beyond the scope of the function or dealing with floating-point precision issues.

Through the introduction of this article, readers will have a more comprehensive and in-depth understanding of trigonometric functions in C, and will be able to use and call trigonometric functions more skillfully to perform various mathematical calculations and application development.

The above is the detailed content of Detailed explanation of trigonometric functions in C++. For more information, please follow other related articles on the PHP Chinese website!