Next: Example while loop: Average, Up: The while statement Previous: Example while loop: Summing

Example while loop: Table of sine function

 

The following program produces a table of x and sin(x) as x takes values 0 to 90 degrees in steps of 5 degrees. Note that the C++ sin function takes an argument in radians, not in degrees. In the program below sin(radian) returns the sine of an angle radian expressed in radians. The mathematical function library will be covered in more detail in section 20.2.

// IEA Oct. 95
// Tabulates x and sin(x)

#include <iostream.h>
#include <math.h>      // because we are going to use
                       // a mathematical function
void main()
{
  const float degtorad = M_PI/180;  // convert degrees
                                    // to radians
  int degree = 0;      // initialise degrees to zero
  float radian;        // radian equivalent of degree
      // Output headings
  cout << endl << "Degrees" << "   sin(degrees)"
       << endl;
      // Now loop
  while (degree <= 90)
    {
      radian = degree * degtorad;  // convert degrees to
                                   // radians
      cout << endl << "   " << degree << "        "
           << sin(radian);
      degree = degree + 5;  // increment degrees
    }
  cout << endl;
}
Download program.

Note that the mathematical constant $\pi$ is defined in the mathematical library as M_PI.


Next: Example while loop: Average, Up: The while statement Previous: Example while loop: Summing