A summary of the correlation functions of C-language _c language

C language Tan () function: tangent function
header file:

#include <math.h>

The tan () function is used to find the tangent of a given value, and its prototype is:

  Double tan (double x);

The "parameter" x is the given radian value.

Return value returns the tangent value of x.

Note that when compiling with GCC, please join-LM.

Take a look at the following code:

#include <math.h>
Main () {
  Double answer = tan (0.5);
  printf ("tan (0.5) =%f\n", answer);
}

Output results:

Tan (0.5) = 0.546302

C language Tanh () function: hyperbola tangent function
header file:

#include <math.h>

Tanh () is used to find the hyperbolic tangent of a number, and its prototype is:

  Double Tanh (double x);

"Parameter" x is a point on the hyperbolic tangent.

Return value returns the hyperbolic tangent of x, with a value ranging from 1 to 1.

The hyperbolic tangent is defined as Sinh (x)/cosh (x), i.e.

Diagram of hyperbolic tangent curve:

Note that when compiling with GCC, please join-LM.

Take a look at the following code:

#include <math.h>
Main () {
  Double answer = tanh (0.5);
  printf ("tanh (0.5) =%f\n", answer);
}

Output results:

Tanh (0.5) = 0.462117

C Language Atan () function: To calculate the tangent value (in radians)
header file:

#include <math.h>

To define a function:

Double Atan (double x);

Function Description: Atan () is used to calculate the inverse tangent value of the parameter x, and then returns the result.

Return value: Returns the result of the calculation between-PI/2 and PI/2.

Note that when compiling with GCC, please join-LM.

Example

#include <math.h>
Main () {
  double angle;
  Angle = Atan (1);
  printf ("angle =%f\n", angle);
}

Perform

Angle = 1.570796

C language atan2 () function: To calculate the tangent value (in radians)
header file:

#include <math.h>

To define a function:

Double atan2 (double y, double x);

Function Description: atan2 () is used to calculate the tangent value of the parameter y/x, and then returns the result.

Return value: Returns the result of the calculation between-PI/2 and PI/2.

Note that when compiling with GCC, please join-LM.

Example

#include <math.h>
Main () {
  double angle;
  Angle = atan2 (1, 2);
  printf ("angle =%f\n", angle);
}

Perform

Angle = 0.463648