Thread: Function and arguement help

I am new to C programming and having a hard time writing this program. If somebody can help it would great. This program ask the user for initial velocity and initial angle, then must calculate the max distance, max height and total travel time. The "requirements " must use at least 3 function not including the main function.

Code:

#include <stdio.h>
#include <stdlib.h>
#include <math.h>


int totaltraveltime(float velocity,float angle,float gravity); 
int peakheight(float velocity,float angle,float gravity);
int range(float velocity,float angle,float gravity);


int main(void)
{
    float initial_velocity=0;
    float initial_angle=0;
    float gravity=9.8;
    float max_distance;
    float max_height;
    float duration;
    
    printf("please enter initial velocity\n");
    
    scanf("%f",&initial_velocity);
    
    printf("please enter initial angle\n");
    
    scanf("%f",&initial_angle);
    
    max_distance = range(initial_velocity,initial_angle,gravity);
    
    max_height = peakheight(initial_velocity,initial_angle,gravity);
    
    duration = totaltraveltime(initial_velocity,initial_angle,gravity);
    
    
  system("PAUSE");	
  return 0;
}
     
     int totaltraveltime(float velocity,float angle)
 { 
     duration= 2*((initial_velocity)*sin(initial_angle))/gravity;

     return duration;
 }
     int peakheight(float velocity,float angle,float gravity)
 {
     max_height=((initial_velocity)*sin(pow)(initial_angle))/(2*gravity);
    
    return max_height;
 } 
    int range(float velocity,float angle,float gravity)
 {   
      max_distance=((pow)(initial_velocity)*sin(2*initial_angle))/gravity;
  
    return max_distance;
 }

So What's the problem?

Code:

int totaltraveltime(float velocity,float angle,float gravity); 


     int totaltraveltime(float velocity,float angle)
 { 
     duration= 2*((initial_velocity)*sin(initial_angle))/gravity;

     return duration;
 }

Read your text book on functions!!!!

The text book that is issued to the class is for Matlab. My teacher don't want us to use Matlab yet. So most information i get is over the internet

Originally Posted by timbean

I am new to C programming and having a hard time writing this program. If somebody can help it would great. This program ask the user for initial velocity and initial angle, then must calculate the max distance, max height and total travel time. The "requirements " must use at least 3 function not including the main function.

Code:

#include <stdio.h>
#include <stdlib.h>
#include <math.h>


int totaltraveltime(float velocity,float angle,float gravity); 
int peakheight(float velocity,float angle,float gravity);
int range(float velocity,float angle,float gravity);


int main(void)
{
    float initial_velocity=0;
    float initial_angle=0;
    float gravity=9.8;
    float max_distance;
    float max_height;
    float duration;
    
    printf("please enter initial velocity\n");
    
    scanf("%f",&initial_velocity);
    
    printf("please enter initial angle\n");
    
    scanf("%f",&initial_angle);
    
    max_distance = range(initial_velocity,initial_angle,gravity);
    
    max_height = peakheight(initial_velocity,initial_angle,gravity);
    
    duration = totaltraveltime(initial_velocity,initial_angle,gravity);
    
    
  system("PAUSE");	
  return 0;
}
     
     int totaltraveltime(float velocity,float angle)
 { 
     duration= 2*((initial_velocity)*sin(initial_angle))/gravity;

     return duration;
 }
     int peakheight(float velocity,float angle,float gravity)
 {
     max_height=((initial_velocity)*sin(pow)(initial_angle))/(2*gravity);
    
    return max_height;
 } 
    int range(float velocity,float angle,float gravity)
 {   
      max_distance=((pow)(initial_velocity)*sin(2*initial_angle))/gravity;
  
    return max_distance;
 }

Is that the way I need to define the prototype?

I do not know what I am doing wrong =(

1. When i compile I get a error message on line 40. 'conflicting types for totaltraveltime'


2. I have my formula = to duration.

Code:

 int totaltraveltime(float velocity,float angle)
     { 
           duration= 2*((initial_velocity)*sin(initial_angle))/gravity;

          return duration;
     }

Will the value i get go inside the "main function"?

Code:

 duration = totaltraveltime(initial_velocity,initial_angle,gravity);

I have no idea where line 40 is, but at a rough guess:

Code:

int totaltraveltime(float velocity,float angle,float gravity);

Code:

int totaltraveltime(float velocity,float angle)

Do those look the same to you?

And that's what return does -- it returns that value to the caller. You don't have to use the same name if you don't want to, as the duration that's inside the function and the duration that's inside main aren't going to be related at all anyway.

Thank You very much. I did not see that.