/*   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;
}