/* Rodney Biggs COP3223 Summer 2005 */
/* prg2.c 06.14.05 */
/* Add functions and a loop to program 1 */
#include <stdio.h>
#include <math.h>
#define PI 3.14159
int root(), trig(); /* Declares the functions root() and trig() as integers */
/* The following lines ask the user to select from three choices. */
/* The program then calls the appropriate function based on the */
/* users input. */
int main(void)
{
int choice; /* Declares choice as an integer variable */
do /* Added for program 2 assignment */
{
/* The following three choices have been put into a box to be more readable */
/* when redisplayed after the calculations. The 3rd choice was added for */
/* the program 2 assignment. */
printf("\n -----------------------------------------------------------");
printf("\n| Please choose an option: |\n");
printf("| |\n");
printf("| 1) Calculate the distance between two points in a plane |\n");
printf("| 2) Calculate the trigonometric function of an angle |\n");
printf("| 3) Exit this program |\n");
printf(" -----------------------------------------------------------\n");
scanf("%d", &choice);
if (choice < 2)
root();
else if (choice == 2)
trig();
else
break ; /* Added for program 2 assignment */
}
while (choice < 3); /* Added for program 2 assignment */
return 0;
}
/* The following function will calculate the distance between two points. */
int root()
{
float x1, y1, x2, y2, distance; /* Defines variables as type float */
/* The following lines of code request the user to input 2 pairs of */
/* numbers. Those numbers are then printed onto the screen in paranthesis. */
/* The numbers are then ran through the distance formula to determine the */
/* distance between the two coordinate points. The resulting distance is */
/* then printed onto the screen with two decimal places. */
printf("\n Please enter any two coordinate pairs. (Ex. x y x y)\n");
scanf("%f%f%f%f", &x1, &y1, &x2, &y2);
printf("\n(%.2f ,%.2f) (%.2f ,%.2f)\n", x1, y1, x2, y2);
distance = sqrt(((x2-x1)*(x2-x1)) + ((y2-y1)*(y2-y1)));
printf("\nDistance = %.2f\n", distance);
return 1;
}
/* The following lines of code will calculate the trigonometric function of an angle */
int trig()
{
float angle_deg, angle_rad; /* Defines variables */
float angle_sin, angle_cos, angle_tan; /* as type float */
/* The following lines of code ask the user to input an angle (in degrees) */
/* and then converts it into radians. The program then finds the sin/cos/tan */
/* of the radian measure of the angle and then prints the results. */
printf("\nPlease enter the angle measure, in degrees.\n");
scanf("%f", &angle_deg);
angle_rad = angle_deg * PI / 180.0;
printf("\nsin(%.1f) = %f\n", angle_deg, angle_sin = sin(angle_rad));
printf("\ncos(%.1f) = %f\n", angle_deg, angle_cos = cos(angle_rad));
printf("\ntan(%.1f) = %f\n", angle_deg, angle_tan = tan(angle_rad));
return 1;
}