Idea for final project

I am trying to come up with an idea for a final project in my C programming class and can't think of a good one.
The program is to be made in Pelles C as a win32 console program and must contain the following:

Must use "functions"
Must use "if" statements
Must contain "loops"
Must have a "menu"
Must end with a "sentinel"
and it must contain at least 150 lines of code.

any ideas on what i should write?
any idea and maybe some hints on how to make the program flow would be much appreciated.

THANKS!

Floyd-Warshall implemented in an iterative way.Set as bonus to class to compute which is the shortest path too.If they know recursion why not let them have fun with a recursive implementation too? ;)
This will be more complex than what you want.
Functions,if/else,loops,menu is there.I do not know what is a sentinel :/

Another idea is the reversi game that this is much heavier project.
It has all the above,plus lists ,save/load and moooore...

How about a "phone book" application? Allow users to enter, delete, or sort the names/numbers (menu), and each selection can be written in its own function. "if" statements and loops would be naturally be required to implement the logic required for such a program.

Quote:

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any idea and maybe some hints on how to make the program flow would be much appreciated.

---

A simple flow chart would help you see the logical flow of the program quite clearly.

To std10093: This is a pretty basic C programming class, as I am only in my second semester and many of this i have not learned yet, building a program like this is too complex for me right now. What we have learned is pretty much the list of things the program must contain, going above and beyond that is outside of my grasp right now. this is regular C not C++ and I don't have any prior experience with any other language. I know, I know, I'm not too advanced yet, but I have to start somewhere.

Quote:

---

Originally Posted by Matticus

How about a "phone book" application? Allow users to enter, delete, or sort the names/numbers (menu), and each selection can be written in its own function. "if" statements and loops would be naturally be required to implement the logic required for such a program.

---

A few problems i see here is when you exit the program all information is lost, defeating the point of trying to store user information in a "phone book" like way since any information typed inside the program does not change the code. I understand the implementation, but I am hoping for a program that has real world application everytime i open the program.

Quote:

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Originally Posted by friedsandwich

A few problems i see here is when you exit the program all information is lost, defeating the point of trying to store user information in a "phone book" like way since any information typed inside the program does not change the code. I understand the implementation, but I am hoping for a program that has real world application everytime i open the program.

---

Are you aware of file operations? You could easily save / load data from a binary file.

std10093 responded to that well.

However, it seems like file I/O might be more difficult than you're ready to handle. Just to note: it could take several dozens of programs worth of experience before you can start writing code with a useful application.

How about this one? A simple [and severely limited] calculator. Select the operation from a menu, enter the two operands, and write a function that performs the selected operation on the numbers entered by the user. Repeat until the user enters a specific value.

Quote:

---

Originally Posted by std10093

Are you aware of file operations? You could easily save / load data from a binary file.

---

I'm not sure how that is done. or even what that means to be honest. Hopefully I don't sound too stupid here I AM just learning programming, this must be a "Win32 Console Program" that i can write at home and/or school and then present it on a different computer without having any other files/programs used to operate the project. The only thing I have been able to think of is some sort of calculator, but with that I don't know where to stop when it comes to types of calculations, so i was hoping for something a little more clear cut with the parameters of the program.

No you are not stupid.You are a beginner ;)

I vote for calculator too.

Quote:

---

Originally Posted by Matticus

std10093 responded to that well.

However, it seems like file I/O might be more difficult than you're ready to handle. Just to note: it could take several dozens of programs worth of experience before you can start writing code with a useful application.

How about this one? A simple [and severely limited] calculator. Select the operation from a menu, enter the two operands, and write a function that performs the selected operation on the numbers entered by the user. Repeat until the user enters a specific value.

---

ha ha didn't read your post before i wrote my last one. That was the only idea i could come up with too. I am just hoping that it's not too limited by just using the <math.h> file and no coding of my own if that makes sense.

Then simply write your own math functions instead of using math.h. It's common, during the learning process, to write functions that mimic standard functions, in order to gain a better understanding of the language.

Yeah i Think this could be a good project. I'm thinking operations of:
addition of x and y, subtraction of x and y, multiplication of x and y, division of x and y, absolute value of x, square root of x, x to the power of y, a bunch of formulas to find the area of different shapes, and possibly finding the GCF of x and y, and the factors of x.......... what else should i add or not have in there?

That's a good start. Just a word of caution - those new to programming tend to start writing all of their code at once, and hit a wall of warnings/errors when they're finally ready to test it. I don't know if this applies to you, but a good development process doesn't seem to be taught as much as it should be. Get the basics working first, and take it step by step. My recommendation:

1. Write a program with a "menu" function. The menu function will print out the menu, receive user input, and return the user input as an integer. Verify that this works correctly.

2. Add an "addition" function to the program, that will be executed when the user enters the appropriate menu selection. Also include user input prompt. Verify that this works correctly.

3. Put the user input and menu selection within a loop. Verify that this works correctly.

4. Expand your program to include "subtraction", "division", and "multiplication" functions. Update the menu and main program loop. Verify that this works correctly.

From here, you can add new menu items and associated function (one at a time), knowing that the structure of the program works correctly, leaving you free to code/troubleshoot each new function on its own.

having a problem with finding the quotient of two numbers.... a switch statement won't allow me to use a double so finding the quotient of 15/4 is coming up with the answer 3... how do i fix this problem?

my code so far.....

Code:

---

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


int main(void)
{
int sum, first_Num, sec_Num, diff, product, quotient;
int choice;
    do
        {
        printf("\nChoose what calculation to perform\n");
        printf("\t1 - Addition\n");
        printf("\t2 - Subtration\n");
        printf("\t3 - Multiplication\n");
        printf("\t4 - Division\n");
        printf("\t5 - Square Root\n");
        printf("\t6 - Exponents\n");
        printf("\t7 - Absolute Value\n");
        printf("\t8 - Area of Shapes\n");
        printf("(Enter a zero to exit) \n");
        printf("What is your choice? ");
        scanf("%d", &choice);


        switch (choice)
        {
            case 1:
            {
                printf("Enter first number: ");
                scanf("%d", &first_Num);
                printf("Enter second number: ");
                scanf("%d", &sec_Num);
                sum = first_Num + sec_Num;
                printf("\nThe sum of %d and %d is %d\n\n", first_Num, sec_Num, sum);
                break;
            }
            case 2:
            {
                printf("Enter first number: ");
                scanf("%d", &first_Num);
                printf("Enter second number: ");
                scanf("%d", &sec_Num);
                diff = first_Num - sec_Num;
                printf("\nThe difference of %d and %d is %d\n\n", first_Num, sec_Num, diff);
                break;
            }
            case 3:
            {
                printf("Enter first number: ");
                scanf("%d", &first_Num);
                printf("Enter second number: ");
                scanf("%d", &sec_Num);
                product = first_Num * sec_Num;
                printf("\nThe product of %d and %d is %d\n\n", first_Num, sec_Num, product);
                break;
            }
            case 4:
            {
                printf("Enter first number: ");
                scanf("%d", &first_Num);
                printf("Enter second number: ");
                scanf("%d", &sec_Num);
                quotient = first_Num / sec_Num;
                printf("\nThe quotient of %d and %d is %d\n\n", first_Num, sec_Num, quotient);
                break;
            }
        }
    }
    while (choice != 0);
return (0);
}

---

I tried using %f, %lf and declaring quotient as a double, it gives me a bad data return

I suggest using modulus "%" to display the remainder and still do just integer division.

Tim S.

Quote:

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Originally Posted by stahta01

I suggest using modulus "%" to display the remainder and still do just integer division.

Tim S.

---

but % will ONLY give me the remainder, I am trying to input 2 numbers and display their quotient even when the result is not a whole number....

use a float a make a cast when you divide

Code:

---

float quotient;
.....

quotient = (float)first_Num / sec_Num;
printf("\nThe quotient of %d and %d is %f\n\n", first_Num, sec_Num, quotient);

---

to complicate things, did u do function pointers? It's a perfect case to use them, if you have not yet studied them does nothing it's just an advice :)
Or you can set up your program in a different way, for example

Code:

---

switch(choice){
case 1: sum(first_Num, sec_Num); break;
case 2:
...

}

---

and write a function for each operation.

Quote:

---

Originally Posted by root

use a float a make a cast when you divide

Code:

---

float quotient;
.....

quotient = (float)first_Num / sec_Num;
printf("\nThe quotient of %d and %d is %f\n\n", first_Num, sec_Num, quotient);

---

---

that is giving me the result of 0.000000 no matter what numbers i enter.

Quote:

---

Originally Posted by root

did u do function pointers? It's a perfect case to use them, if you have not yet studied them does nothing it's just an advice :)

---

yeah we learned about pointers this past week... how would i implement them in this situation?
since a switch statement doesnt allow the use of double do i need to change the whole code to nested if statements instead?

This is what you want?

Code:

---

#include <stdio.h>
#include <math.h> /* for fmod */

int main(void)
{

  float a,b;

  scanf("%f",&a);
  scanf("%f",&b);

  printf("Quotent a/b = %f\n",a/b);
  printf("Quotent a mod b = %f\n",fmod(a,b));

  return 0;
}

---

Comments : Declare numbers as float, read them, divide them and print quotient and remainer(mod).

I found the problem, had to declare all my variables as doubles instead of int except for choice. now I'm having problems inside my 8th case statement which opens a new menu of different shapes to find the area.... any suggestions?

Code:

---

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


int main(void)
{
double sum, first_Num, sec_Num, diff, product, quotient, srt;
int choice, selection;
        do
        {
                printf("\nChoose what calculation to perform\n");
                printf("\t1 - Addition\n");
                printf("\t2 - Subtration\n");
                printf("\t3 - Multiplication\n");
                printf("\t4 - Division\n");
                printf("\t5 - Square Root\n");
                printf("\t6 - Exponents\n");
                printf("\t7 - Absolute Value\n");
                printf("\t8 - Area of Shapes\n");
                printf("(Enter a zero to exit) \n");
                printf("\nMake a selection: ");
                scanf("%d", &choice);


                switch (choice)
                {
                        case 1:
                        {
                                printf("\nEnter first number: ");
                                scanf("%lf", &first_Num);
                                printf("Enter second number: ");
                                scanf("%lf", &sec_Num);
                                sum = first_Num + sec_Num;
                                printf("\nThe sum of %.4f and %.4f is %.4f\n\n", first_Num, sec_Num, sum);
                                break;
                        }
                        case 2:
                        {
                                printf("\nEnter first number: ");
                                scanf("%lf", &first_Num);
                                printf("Enter second number: ");
                                scanf("%lf", &sec_Num);
                                diff = first_Num - sec_Num;
                                printf("\nThe difference of %.4f and %.4f is %.4f\n\n", first_Num, sec_Num, diff);
                                break;
                        }
                        case 3:
                        {
                                printf("\nEnter first number: ");
                                scanf("%lf", &first_Num);
                                printf("Enter second number: ");
                                scanf("%lf", &sec_Num);
                                product = first_Num * sec_Num;
                                printf("\nThe product of %.4f and %.4f is %.4f\n\n", first_Num, sec_Num, product);
                                break;
                        }
                        case 4:
                        {
                                printf("\nEnter first number: ");
                                scanf("%lf", &first_Num);
                                printf("Enter second number: ");
                                scanf("%lf", &sec_Num);
                                quotient = first_Num / sec_Num;
                                printf("\nThe quotient of %.4f and %.4f is %.4f\n\n", first_Num, sec_Num, quotient);
                                break;
                        }
                        case 5:
                        {
                                printf("\nEnter number: ");
                                scanf("%lf", &srt);
                                {
                                        while (srt <= 0)
                                                {
                                              printf("Value must be a positive number\n");
                                                        printf("Enter number: ");
                                                        scanf("%lf", &srt);
                                                }
                                       
                                              printf("The square root of %.4f is %.4f\n", srt, sqrt(srt));
                                }
                                        break;
                        }
                        case 6:
                        {
                                printf("\nEnter base number: ");
                                scanf("%lf", &first_Num);
                                printf("Enter exponent: ");
                                scanf("%lf", &sec_Num);
                                printf("%.4f to the power of %.4f is %.4f", first_Num, sec_Num, pow(first_Num, sec_Num));
                                break;
                        }
                        case 7:
                        {
                                printf("\nEnter number: ");
                                scanf("%lf", &first_Num);
                                printf("The absolute value of %.4f is %.4f", first_Num, fabs(first_Num));
                                break;
                        }
                        case 8:
                        {
                                do
                                {
                                        printf("Find the area of a shape\n");
                                        printf("Which shape?\n");
                                        printf("\t1 - Square\n");
                                        printf("\t2 - Rectangle\n");
                                        printf("\t3 - Parallelogram\n");
                                        printf("\t4 - Trapezoid\n");
                                        printf("\t5 - Circle\n");
                                        printf("\t6 - Ellipse\n");
                                        printf("\t7 - Triangle\n");
                                        printf("\t8 - Go back to previous menu\n");
                                       
                                        printf("Make a selection ");
                                        scanf("%d", &selection);
                                               
                                                switch (selection)
                                                {
                                                        case 1:
                                                        {
                                                                printf("Enter length of a side of the square: ");
                                                                scanf("%lf", first_Num);
                                                                while (first_Num <= 0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number");
                                                                        printf("Enter length of a side of the square: ");
                                                                        scanf("%lf", first_Num);
                                                                }
                                                               
                                                                printf("The area of the square is %.4f\n\n", (first_Num * first_Num));
                                                                break;
                                                               
                                                               
                                                        }
                                                }
                                                break;
                                        }
                                while (selection != 8);
                        }
                }
        }
        while (choice != 0);
return (0);
}

---

Code:

---

scanf("%lf", first_Num)

---

scanf requires you to pass the adress of the variable, thus &first_Num

Tip : When you report an error, it is good to give more information.What is the error?What kind of an error is that?Where it happens( you said only this).

Or even better post what the compiler says ;) He is not a lier not a dummy. He is clever ;)

Quote:

---

Originally Posted by std10093

Code:

---

scanf("%lf", first_Num)

---

scanf requires you to pass the adress of the variable, thus &first_Num

Tip : When you report an error, it is good to give more information.What is the error?What kind of an error is that?Where it happens( you said only this).

Or even better post what the compiler says ;) He is not a lier not a dummy. He is clever ;)

---

HA HA HA oh man i feel stupid. yeah i forgot the damn ampersand. the compiler wasn't giving me any errors that's why i was so confused! thanks for correcting my stupidity!

Quote:

---

Originally Posted by friedsandwich

HA HA HA oh man i feel stupid. yeah i forgot the damn ampersand. the compiler wasn't giving me any errors that's why i was so confused! thanks for correcting my stupidity!

---

I would not call it stupidity ;) You are still learning (like all of us ;) )

here is my code any suggestions on what i should add?
all input is much appreciated!!

Code:

---

#include <stdio.h>
#include <math.h>
#define PI 3.14159


int main(void)
{
double sum, first_Num, sec_Num, third_Num, diff, product, quotient, srt, area, rad1, rad2, base, height;
int choice, selection;
        do
        {
                printf("\nChoose what calculation to perform\n");
                printf("\t1 - Addition\n");
                printf("\t2 - Subtration\n");
                printf("\t3 - Multiplication\n");
                printf("\t4 - Division\n");
                printf("\t5 - Square Root\n");
                printf("\t6 - Exponents\n");
                printf("\t7 - Absolute Value\n");
                printf("\t8 - Area of Shapes\n");
                printf("(Enter a zero to exit) \n");
                printf("\nMake a selection: ");
                scanf("%d", &choice);


                switch (choice)
                {
                        case 1:
                        {
                                printf("\nEnter first number: ");
                                scanf("%lf", &first_Num);
                                printf("Enter second number: ");
                                scanf("%lf", &sec_Num);
                                sum = first_Num + sec_Num;
                                printf("\nThe sum of %.4f and %.4f is %.4f\n\n", first_Num, sec_Num, sum);
                                break;
                        }
                        case 2:
                        {
                                printf("\nEnter first number: ");
                                scanf("%lf", &first_Num);
                                printf("Enter second number: ");
                                scanf("%lf", &sec_Num);
                                diff = first_Num - sec_Num;
                                printf("\nThe difference of %.4f and %.4f is %.4f\n\n", first_Num, sec_Num, diff);
                                break;
                        }
                        case 3:
                        {
                                printf("\nEnter first number: ");
                                scanf("%lf", &first_Num);
                                printf("Enter second number: ");
                                scanf("%lf", &sec_Num);
                                product = first_Num * sec_Num;
                                printf("\nThe product of %.4f and %.4f is %.4f\n\n", first_Num, sec_Num, product);
                                break;
                        }
                        case 4:
                        {
                                printf("\nEnter first number: ");
                                scanf("%lf", &first_Num);
                                printf("Enter second number: ");
                                scanf("%lf", &sec_Num);
                                quotient = first_Num / sec_Num;
                                printf("\nThe quotient of %.4f and %.4f is %.4f\n\n", first_Num, sec_Num, quotient);
                                break;
                        }
                        case 5:
                        {
                                printf("\nEnter number: ");
                                scanf("%lf", &srt);
                                {
                                        while (srt <= 0)
                                                {
                                              printf("ERROR!! Value must be a positive number\n\n");
                                                        printf("Enter number: ");
                                                        scanf("%lf", &srt);
                                                }
                                       
                                              printf("\nThe square root of %.4f is %.4f\n", srt, sqrt(srt));
                                }
                                        break;
                        }
                        case 6:
                        {
                                printf("\nEnter base number: ");
                                scanf("%lf", &first_Num);
                                printf("Enter exponent: ");
                                scanf("%lf", &sec_Num);
                                printf("\n%.4f to the power of %.4f is %.4f\n\n", first_Num, sec_Num, pow(first_Num, sec_Num));
                                break;
                        }
                        case 7:
                        {
                                printf("\nEnter number: ");
                                scanf("%lf", &first_Num);
                                printf("\nThe absolute value of %.4f is %.4f\n\n", first_Num, fabs(first_Num));
                                break;
                        }
                        case 8:
                        {
                                do
                                {
                                        printf("\nFIND THE AREA OF A SHAPE\n\n");
                                        printf("Which shape?\n");
                                        printf("\t1 - Square\n");
                                        printf("\t2 - Rectangle\n");
                                        printf("\t3 - Parallelogram\n");
                                        printf("\t4 - Trapezoid\n");
                                        printf("\t5 - Circle\n");
                                        printf("\t6 - Ellipse\n");
                                        printf("\t7 - Triangle\n");
                                        printf("\t8 - Go back to previous menu\n");
                                       
                                        printf("\nMake a selection: ");
                                        scanf("%d", &selection);
                                               
                                                switch (selection)
                                                {
                                                        case 1:
                                                        {
                                                                printf("\nArea Of A Square\n");
                                                                printf("\nEnter length of a side of the square: ");
                                                                scanf("%lf", &first_Num);
                                                                while (first_Num <= 0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter length of a side of the square: ");
                                                                        scanf("%lf", &first_Num);
                                                                }
                                                                area = first_Num * first_Num;
                                                                printf("\nThe area of a square with a side of %.4f is %.4f\n\n", first_Num, area);
                                                                break;
                                                        }
                                                        case 2:
                                                        {
                                                                printf("\nArea Of A Rectangle\n");
                                                                printf("\nEnter width: ");
                                                                scanf("%lf", &first_Num);
                                                                while (first_Num <=0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter width: ");
                                                                        scanf("%lf", &first_Num);
                                                                }
                                                                printf("Enter height: ");
                                                                scanf("%lf", &sec_Num);
                                                                while(sec_Num <= 0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter height: ");
                                                                        scanf("%lf", &sec_Num);
                                                                }
                                                                area = first_Num * sec_Num;
                                                                printf("\nThe area of a rectagle with sides of %.4f and %.4f is %.4f\n\n", first_Num, sec_Num, area);
                                                                break;
                                                        }
                                                        case 3:
                                                        {
                                                                printf("\nArea Of A Parallelogram");
                                                                printf("\nEnter base: ");
                                                                scanf("%lf", &first_Num);
                                                                while (first_Num <=0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter base: ");
                                                                        scanf("%lf", &first_Num);
                                                                }
                                                                printf("\nEnter height: ");
                                                                scanf("%lf", &sec_Num);
                                                                while(sec_Num <= 0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter height: ");
                                                                        scanf("%lf", &sec_Num);
                                                                }
                                                                area = first_Num * sec_Num;
                                                                printf("\nThe area of a parallelogram with sides of %.4f and %.4f is %.4f\n\n", first_Num, sec_Num, area);
                                                                break;
                                                        }
                                                        case 4:
                                                        {
                                                                printf("\nArea Of A Trapezoid");
                                                                printf("\nEnter base-1: ");
                                                                scanf("%lf", &first_Num);
                                                                while (first_Num <=0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter base-1: ");
                                                                        scanf("%lf", &first_Num);
                                                                }
                                                                printf("\nEnter base-2: ");
                                                                scanf("%lf", &sec_Num);
                                                                while(sec_Num <= 0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter base-2: ");
                                                                        scanf("%lf", &sec_Num);
                                                                }
                                                                printf("\nEnter height: ");
                                                                scanf("%lf", &third_Num);
                                                                while(third_Num <= 0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter height: ");
                                                                        scanf("%lf", &third_Num);
                                                                }
                                                                area = (third_Num/2) * (first_Num + sec_Num);
                                                                printf("\nThe area of a trapezoid with a base-1 of %.4f, a base-2 %.4f, and a height of %.4f is %.4f\n\n", first_Num, sec_Num, third_Num, area);
                                                                break;
                                                        }
                                                        case 5:
                                                        {
                                                                printf("\nArea Of A Circle\n");
                                                                printf("\nEnter the radius: ");
                                                                scanf("%lf", &rad1);
                                                                while(rad1 <= 0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter the radius: ");
                                                                        scanf("%lf", &rad1);
                                                                }
                                                                area = (rad1 * rad1) * PI;
                                                                printf("The area of a circle with a radius of %.4f is %.4f\n\n", rad1, area);
                                                                break;
                                                        }
                                                        case 6:
                                                        {
                                                                printf("\nArea Of An Ellipse");
                                                                printf("\nEnter radius-1: ");
                                                                scanf("%lf", &rad1);
                                                                while(rad1 <= 0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter radius-1: ");
                                                                        scanf("%lf", &rad1);
                                                                }
                                                                printf("\nEnter radius-2: ");
                                                                scanf("%lf", &rad2);
                                                                while(rad2 <= 0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter radius-2: ");
                                                                        scanf("%lf", &rad2);
                                                                }
                                                                area = (rad1 * rad2) * PI;
                                                                printf("The area of an ellipse with a radius-1 of %.4f and a radius-2 of %.4f is %.4f", rad1, rad2, area);
                                                                break;
                                                        }
                                                        case 7:
                                                        {
                                                                printf("\nArea Of A Triangle");
                                                                printf("\nEnter base: ");
                                                                scanf("%lf", &base);
                                                                while(base<=0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter base: ");
                                                                        scanf("%lf", &base);
                                                                }
                                                                printf("Enter height: ");
                                                                scanf("%lf", &height);
                                                                while(height<=0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter height: ");
                                                                        scanf("%lf", &height);
                                                                }
                                                                area = (base * height) / 2;
                                                                printf("The area of a triangle with a base of %.4f and a height of %.4f is %.4f", base, height, area);
                                                                break;
                                                        }
                                                        default:
                                                        {
                                                                if (selection !=8)
                                                                {
                                                                        printf("\nYour selection was not from the menu\n");
                                                                        printf("Please try again.\n\n");
                                                                }
                                                                break;
                                                        }
                                                }
                                                break;


                                        }


                                while (selection != 8);
                       
                        }
                        default:
                        {       
                                if (choice != 0)
                                {
                                        printf("\nYour selection was not from the menu\n");
                                        printf("Please try again.\n\n");
                                }
                                break;
                        }
                }
        }
        while (choice != 0);
return (0);
}

---

I'm thinking of adding volume formulas too. maybe a way to find the factors of a number but i'm not sure yet how to do that...

Before adding functionality , test functionality that you already have!

For example in case of division...the user may input as a second number zero (by accident or not ) .What will happen? Probably won't crash, but you should take care of situations like that.I suggest you run it and see what happens ;)

Hey man. I like your code, in fact, I was going to do something like your work but my professor challenged me with this: My calc has to scan the input as a string and then parse the string to figure out what belongs where.

Input sample: 3+5*6-4/2+6*9
Output sample: 85

So far, no luck. I was just able to make the program differentiate between numbers and operators, but I still need to do a lot of work! If you have any ideas, please let me know too OP.

If I get my code to work, feel free to add it to your calc when it's done :)

Quote:

---

Originally Posted by Icekilla

Hey man. I like your code, in fact, I was going to do something like your work but my professor challenged me with this: My calc has to scan the input as a string and then parse the string to figure out what belongs where.

Input sample: 3+5*6-4/2+6*9
Output sample: 85

So far, no luck. I was just able to make the program differentiate between numbers and operators, but I still need to do a lot of work! If you have any ideas, please let me know too OP.

If I get my code to work, feel free to add it to your calc when it's done :)

---

yeah that's what i don't like about my code. the fact that you can only do 1 operation kinda makes it less useful if i have an equation to solve. the best part of my code, imo, is the formulas for area, im also doing the same thing for volumes too. if i can come up with a code like you are trying to that would probably save a lot of memory, (which doesnt matter since my code is built for a pc not an embedded system though) but would add a lot more functionality. let me know what you come up with, I'll keep my code up to date with any changes i make also.

And one more suggestion: Instead of defining Pi, use the already available function in math.h: M_PI.

Quote:

---

Originally Posted by Icekilla

And one more suggestion: Instead of defining Pi, use the already available function in math.h: M_PI.

---

didnt know about that. good idea!


hmmm my compiler isnt allowing M_PI as a constant?

Quote:

---

Originally Posted by Icekilla

Either way, what compiler are you using?

---

Pelles c

Quote:

---

Originally Posted by Icekilla

Try something like Code::Blocks. It's much better.

---

I use pelles because thats what we use at school. Wouldn't mind getting familiarized with another compiler though. Thanks for the suggestion ill try it out

Useless postcount increasing posts deleted
Click it, read it.

Quote:

---

Originally Posted by friedsandwich

didnt know about that. good idea!


hmmm my compiler isnt allowing M_PI as a constant?

---

You have to include the math library

Code:

---

#include <math.h>

---

Quote:

---

Originally Posted by Salem

Useless postcount increasing posts deleted
Click it, read it.

---

@fried A way of posting at once and answering more than one quotes can be done like this :
On the botom of every post, on the right corner there is something like a border with double quotes as its contents.If you click it a "tick" will appear on the corresponding post.You can do that for multiple posts.Then go to the last you "ticked" and click on Reply With Quote, as would do normally .Then the forum automatically will create all the quotes you ticked in one answer.You can see that every "ticked"-post is appearing on your answer-post form wrapped with QUOTE tags :)

Quote:

---

Originally Posted by std10093

You have to include the math library

Code:

---

#include <math.h>

---

---

I have the math.h included......?

Can you please show me your code? :)

Quote:

---

Originally Posted by std10093

Can you please show me your code? :)

---

sure thing

Code:

---

#include <stdio.h>
#include <math.h>
#define PI 3.14159

int main(void)
{
double sum, first_Num, sec_Num, third_Num,
diff, product, quotient, srt, area, rad1, rad2, base, height;
int choice,
selection;
do
{
printf("\nChoose what calculation to
perform\n");
printf("\t1 - Addition\n");
printf("\t2 -
Subtration\n");
printf("\t3 - Multiplication\n");
printf("\t4 -
Division\n");
printf("\t5 - Square Root\n");
printf("\t6 -
Exponents\n");
printf("\t7 - Absolute Value\n");
printf("\t8 - Area of
Shapes\n");
printf("(Enter a zero to exit) \n");
printf("\nMake a
selection: ");
scanf("%d", &choice);

switch (choice)
{
case
1:
{
printf("\nEnter first number: ");
scanf("%lf",
&first_Num);
printf("Enter second number: ");
scanf("%lf",
&sec_Num);
sum = first_Num + sec_Num;
printf("\nThe sum of %f and %f
is %.4f\n\n", first_Num, sec_Num, sum);
break;
}
case
2:
{
printf("\nEnter first number: ");
scanf("%lf",
&first_Num);
printf("Enter second number: ");
scanf("%lf",
&sec_Num);
diff = first_Num - sec_Num;
printf("\nThe difference of
%.4f and %.4f is %.4f\n\n", first_Num, sec_Num, diff);
break;
}
case
3:
{
printf("\nEnter first number: ");
scanf("%lf",
&first_Num);
printf("Enter second number: ");
scanf("%lf",
&sec_Num);
product = first_Num * sec_Num;
printf("\nThe product of
%.4f and %.4f is %.4f\n\n", first_Num, sec_Num, product);
break;
}
case
4:
{
printf("\nEnter first number: ");
scanf("%lf",
&first_Num);
printf("Enter second number: ");
scanf("%lf",
&sec_Num);
quotient = first_Num / sec_Num;
printf("\nThe quotient of
%.4f and %.4f is %.4f\n\n", first_Num, sec_Num,
quotient);
break;
}
case 5:
{
printf("\nEnter number:
");
scanf("%lf", &srt);
{
                                       
while (srt <= 0)
{
                                             
printf("ERROR!! Value must be a positive number\n\n");
printf("Enter number:
");
scanf("%lf", &srt);
}
                                       

                                              printf("\nThe square root of
%.4f is %.4f\n", srt,
sqrt(srt));
}
                                        break;
}
case
6:
{
printf("\nEnter base number: ");
scanf("%lf",
&first_Num);
printf("Enter exponent: ");
scanf("%lf",
&sec_Num);
printf("\n%.4f to the power of %.4f is %.4f\n\n", first_Num,
sec_Num, pow(first_Num, sec_Num));
break;
}
case
7:
{
printf("\nEnter number: ");
scanf("%lf",
&first_Num);
printf("\nThe absolute value of %.4f is %.4f\n\n",
first_Num, fabs(first_Num));
break;
}
case
8:
{
do
{
printf("\nFIND THE AREA OF A SHAPE\n\n");
printf("Which
shape?\n");
printf("\t1 - Square\n");
printf("\t2 -
Rectangle\n");
printf("\t3 - Parallelogram\n");
printf("\t4 -
Trapezoid\n");
printf("\t5 - Circle\n");
printf("\t6 -
Ellipse\n");
printf("\t7 - Triangle\n");
printf("\t8 - Go back to previous
menu\n");

printf("\nMake a selection: ");
scanf("%d",
&selection);

switch (selection)
{
case 1:

{
printf("\nArea Of A Square\n");
printf("\nEnter length of a side of
the square: ");
scanf("%lf", &first_Num);
while (first_Num <=
0)
{
printf("ERROR!! Distance must be a positive
number\n\n");
printf("Enter length of a side of the square:
");
scanf("%lf", &first_Num);
}
area = first_Num *
first_Num;
printf("\nThe area of a square with a side of %.4f is %.4f\n\n",
first_Num, area);
break;
}
case 2:
{
printf("\nArea Of A
Rectangle\n");
printf("\nEnter width: ");
scanf("%lf",
&first_Num);
while (first_Num <=0)
{
printf("ERROR!! Distance
must be a positive number\n\n");
printf("Enter width: ");
scanf("%lf",
&first_Num);
}
printf("Enter height: ");
scanf("%lf",
&sec_Num);
while(sec_Num <= 0)
{
printf("ERROR!! Distance must
be a positive number\n\n");
printf("Enter height: ");
scanf("%lf",
&sec_Num);
}
area = first_Num * sec_Num;
printf("\nThe area of a
rectagle with sides of %.4f and %.4f is %.4f\n\n", first_Num, sec_Num,
area);
break;
}
case 3:
{
printf("\nArea Of A
Parallelogram");
printf("\nEnter base: ");
scanf("%lf",
&first_Num);
while (first_Num <=0)
{
printf("ERROR!! Distance
must be a positive number\n\n");
printf("Enter base: ");
scanf("%lf",
&first_Num);
}
printf("\nEnter height: ");
scanf("%lf",
&sec_Num);
while(sec_Num <= 0)
{
printf("ERROR!! Distance must
be a positive number\n\n");
printf("Enter height: ");
scanf("%lf",
&sec_Num);
}
area = first_Num * sec_Num;
printf("\nThe area of a
parallelogram with sides of %.4f and %.4f is %.4f\n\n", first_Num, sec_Num,
area);
break;
}
case 4:
{
printf("\nArea Of A
Trapezoid");
printf("\nEnter base-1: ");
scanf("%lf",
&first_Num);
while (first_Num <=0)
{
printf("ERROR!! Distance
must be a positive number\n\n");
printf("Enter base-1: ");
scanf("%lf",
&first_Num);
}
printf("\nEnter base-2: ");
scanf("%lf",
&sec_Num);
while(sec_Num <= 0)
{
printf("ERROR!! Distance must
be a positive number\n\n");
printf("Enter base-2: ");
scanf("%lf",
&sec_Num);
}
printf("\nEnter height: ");
scanf("%lf",
&third_Num);
while(third_Num <= 0)
{
printf("ERROR!! Distance
must be a positive number\n\n");
printf("Enter height: ");
scanf("%lf",
&third_Num);
}
area = (third_Num/2) * (first_Num +
sec_Num);
printf("\nThe area of a trapezoid with a base-1 of %.4f, a base-2
%.4f, and a height of %.4f is %.4f\n\n", first_Num, sec_Num, third_Num,
area);
break;
}
case 5:
{
printf("\nArea Of A
Circle\n");
printf("\nEnter the radius: ");
scanf("%lf",
&rad1);
while(rad1 <= 0)
{
printf("ERROR!! Distance must be a
positive number\n\n");
printf("Enter the radius: ");
scanf("%lf",
&rad1);
}
area = (rad1 * rad1) * PI;
printf("The area of a circle
with a radius of %.4f is %.4f\n\n", rad1, area);
break;
}
case
6:
{
printf("\nArea Of An Ellipse");
printf("\nEnter radius-1:
");
scanf("%lf", &rad1);
while(rad1 <= 0)
{
printf("ERROR!!
Distance must be a positive number\n\n");
printf("Enter radius-1:
");
scanf("%lf", &rad1);
}
printf("\nEnter radius-2:
");
scanf("%lf", &rad2);
while(rad2 <= 0)
{
printf("ERROR!!
Distance must be a positive number\n\n");
printf("Enter radius-2:
");
scanf("%lf", &rad2);
}
area = (rad1 * rad2) *
PI;
printf("The area of an ellipse with a radius-1 of %.4f and a radius-2 of
%.4f is %.4f", rad1, rad2, area);
break;
}
case
7:
{
printf("\nArea Of A Triangle");
printf("\nEnter base:
");
scanf("%lf", &base);
while(base<=0)
{
printf("ERROR!!
Distance must be a positive number\n\n");
printf("Enter base:
");
scanf("%lf", &base);
}
printf("Enter height:
");
scanf("%lf", &height);
while(height<=0)
{
printf("ERROR!!
Distance must be a positive number\n\n");
printf("Enter height:
");
scanf("%lf", &height);
}
area = (base * height) /
2;
printf("The area of a triangle with a base of %.4f and a height of %.4f is
%.4f", base, height, area);
break;
}
default:
{
if (selection
!=8)
{
printf("\nYour selection was not from the
menu\n");
printf("Please try again.\n\n");
}

break;
}
}
break;

}while (selection !=
8);
break;
}
default:
{
if (choice != 0)
{
printf("\nYour
selection was not from the menu\n");
printf("Please try
again.\n\n");
}
break;
}
}
}
while (choice != 0);
return
(0);
}

---

I removed #define PI 3.14159 and changed my PI variables to M_PI and it didn't allow it as a constant,

400+ lines of unindented code - no thanks!

Here, read this
SourceForge.net: Indentation - cpwiki

Quote:

---

Originally Posted by Salem

400+ lines of unindented code - no thanks!

Here, read this
SourceForge.net: Indentation - cpwiki

---

oh geez, sorry that my formatting was messed up while pulling this code of my gmail drive.....

Code:

---

#include <stdio.h>
#include <math.h>
#define PI 3.14159
 
int main(void)
{
double sum, first_Num, sec_Num, third_Num, diff, product, quotient, srt, area, rad1, rad2, base, height;
int choice, selection;
        do
        {
                printf("\nChoose what calculation to perform\n");
                printf("\t1 - Addition\n");
                printf("\t2 - Subtration\n");
                printf("\t3 - Multiplication\n");
                printf("\t4 - Division\n");
                printf("\t5 - Square Root\n");
                printf("\t6 - Exponents\n");
                printf("\t7 - Absolute Value\n");
                printf("\t8 - Area of Shapes\n");
                printf("(Enter a zero to exit) \n");
                printf("\nMake a selection: ");
                scanf("%d", &choice);
 
                switch (choice)
                {
                        case 1: 
                        {
                                printf("\nEnter first number: ");
                                scanf("%lf", &first_Num);
                                printf("Enter second number: ");
                                scanf("%lf", &sec_Num);
                                sum = first_Num + sec_Num;
                                printf("\nThe sum of %.4f and %.4f is %.4f\n\n", first_Num, sec_Num, sum);
                                break;
                        }
                        case 2:
                        {
                                printf("\nEnter first number: ");
                                scanf("%lf", &first_Num);
                                printf("Enter second number: ");
                                scanf("%lf", &sec_Num);
                                diff = first_Num - sec_Num;
                                printf("\nThe difference of %.4f and %.4f is %.4f\n\n", first_Num, sec_Num, diff);
                                break;
                        }
                        case 3:
                        {
                                printf("\nEnter first number: ");
                                scanf("%lf", &first_Num);
                                printf("Enter second number: ");
                                scanf("%lf", &sec_Num);
                                product = first_Num * sec_Num;
                                printf("\nThe product of %.4f and %.4f is %.4f\n\n", first_Num, sec_Num, product);
                                break;
                        }
                        case 4:
                        {
                                printf("\nEnter first number: ");
                                scanf("%lf", &first_Num);
                                printf("Enter second number: ");
                                scanf("%lf", &sec_Num);
                                quotient = first_Num / sec_Num;
                                printf("\nThe quotient of %.4f and %.4f is %.4f\n\n", first_Num, sec_Num, quotient);
                                break;
                        }
                        case 5:
                        {
                                printf("\nEnter number: ");
                                scanf("%lf", &srt);
                                {
                                        while (srt <= 0)
                                                {
                                              printf("ERROR!! Value must be a positive number\n\n");
                                                        printf("Enter number: ");
                                                        scanf("%lf", &srt);
                                                }
                                       
                                              printf("\nThe square root of %.4f is %.4f\n", srt, sqrt(srt));
                                }
                                        break;
                        }
                        case 6:
                        {
                                printf("\nEnter base number: ");
                                scanf("%lf", &first_Num);
                                printf("Enter exponent: ");
                                scanf("%lf", &sec_Num);
                                printf("\n%.4f to the power of %.4f is %.4f\n\n", first_Num, sec_Num, pow(first_Num, sec_Num));
                                break;
                        }
                        case 7:
                        {
                                printf("\nEnter number: ");
                                scanf("%lf", &first_Num);
                                printf("\nThe absolute value of %.4f is %.4f\n\n", first_Num, fabs(first_Num));
                                break;
                        }
                        case 8:
                        {
                                do
                                {
                                        printf("\nFIND THE AREA OF A SHAPE\n\n");
                                        printf("Which shape?\n");
                                        printf("\t1 - Square\n");
                                        printf("\t2 - Rectangle\n");
                                        printf("\t3 - Parallelogram\n");
                                        printf("\t4 - Trapezoid\n");
                                        printf("\t5 - Circle\n");
                                        printf("\t6 - Ellipse\n");
                                        printf("\t7 - Triangle\n");
                                        printf("\t8 - Go back to previous menu\n");
                                       
                                        printf("\nMake a selection: ");
                                        scanf("%d", &selection);
                                               
                                                switch (selection)
                                                {
                                                        case 1: 
                                                        {
                                                                printf("\nArea Of A Square\n");
                                                                printf("\nEnter length of a side of the square: ");
                                                                scanf("%lf", &first_Num);
                                                                while (first_Num <= 0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter length of a side of the square: ");
                                                                        scanf("%lf", &first_Num);
                                                                }
                                                                area = first_Num * first_Num;
                                                                printf("\nThe area of a square with a side of %.4f is %.4f\n\n", first_Num, area);
                                                                break;
                                                        }
                                                        case 2:
                                                        {
                                                                printf("\nArea Of A Rectangle\n");
                                                                printf("\nEnter width: ");
                                                                scanf("%lf", &first_Num);
                                                                while (first_Num <=0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter width: ");
                                                                        scanf("%lf", &first_Num);
                                                                }
                                                                printf("Enter height: ");
                                                                scanf("%lf", &sec_Num);
                                                                while(sec_Num <= 0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter height: ");
                                                                        scanf("%lf", &sec_Num);
                                                                }
                                                                area = first_Num * sec_Num;
                                                                printf("\nThe area of a rectagle with sides of %.4f and %.4f is %.4f\n\n", first_Num, sec_Num, area);
                                                                break;
                                                        }
                                                        case 3:
                                                        {
                                                                printf("\nArea Of A Parallelogram");
                                                                printf("\nEnter base: ");
                                                                scanf("%lf", &first_Num);
                                                                while (first_Num <=0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter base: ");
                                                                        scanf("%lf", &first_Num);
                                                                }
                                                                printf("\nEnter height: ");
                                                                scanf("%lf", &sec_Num);
                                                                while(sec_Num <= 0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter height: ");
                                                                        scanf("%lf", &sec_Num);
                                                                }
                                                                area = first_Num * sec_Num;
                                                                printf("\nThe area of a parallelogram with sides of %.4f and %.4f is %.4f\n\n", first_Num, sec_Num, area);
                                                                break;
                                                        }
                                                        case 4:
                                                        {
                                                                printf("\nArea Of A Trapezoid");
                                                                printf("\nEnter base-1: ");
                                                                scanf("%lf", &first_Num);
                                                                while (first_Num <=0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter base-1: ");
                                                                        scanf("%lf", &first_Num);
                                                                }
                                                                printf("\nEnter base-2: ");
                                                                scanf("%lf", &sec_Num);
                                                                while(sec_Num <= 0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter base-2: ");
                                                                        scanf("%lf", &sec_Num);
                                                                }
                                                                printf("\nEnter height: ");
                                                                scanf("%lf", &third_Num);
                                                                while(third_Num <= 0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter height: ");
                                                                        scanf("%lf", &third_Num);
                                                                }
                                                                area = (third_Num/2) * (first_Num + sec_Num);
                                                                printf("\nThe area of a trapezoid with a base-1 of %.4f, a base-2 %.4f, and a height of %.4f is %.4f\n\n", first_Num, sec_Num, third_Num, area);
                                                                break;
                                                        }
                                                        case 5:
                                                        {
                                                                printf("\nArea Of A Circle\n");
                                                                printf("\nEnter the radius: ");
                                                                scanf("%lf", &rad1);
                                                                while(rad1 <= 0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter the radius: ");
                                                                        scanf("%lf", &rad1);
                                                                }
                                                                area = (rad1 * rad1) * PI;
                                                                printf("The area of a circle with a radius of %.4f is %.4f\n\n", rad1, area);
                                                                break;
                                                        } 
                                                        case 6:
                                                        {
                                                                printf("\nArea Of An Ellipse");
                                                                printf("\nEnter radius-1: ");
                                                                scanf("%lf", &rad1);
                                                                while(rad1 <= 0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter radius-1: ");
                                                                        scanf("%lf", &rad1);
                                                                }
                                                                printf("\nEnter radius-2: ");
                                                                scanf("%lf", &rad2);
                                                                while(rad2 <= 0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter radius-2: ");
                                                                        scanf("%lf", &rad2);
                                                                }
                                                                area = (rad1 * rad2) * PI;
                                                                printf("The area of an ellipse with a radius-1 of %.4f and a radius-2 of %.4f is %.4f", rad1, rad2, area);
                                                                break;
                                                        }
                                                        case 7:
                                                        {
                                                                printf("\nArea Of A Triangle");
                                                                printf("\nEnter base: ");
                                                                scanf("%lf", &base);
                                                                while(base<=0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter base: ");
                                                                        scanf("%lf", &base);
                                                                }
                                                                printf("Enter height: ");
                                                                scanf("%lf", &height);
                                                                while(height<=0)
                                                                {
                                                                        printf("ERROR!! Distance must be a positive number\n\n");
                                                                        printf("Enter height: ");
                                                                        scanf("%lf", &height);
                                                                }
                                                                area = (base * height) / 2;
                                                                printf("The area of a triangle with a base of %.4f and a height of %.4f is %.4f", base, height, area);
                                                                break;
                                                        }
                                                        default:
                                                        {
                                                                if (selection !=8)
                                                                {
                                                                        printf("\nYour selection was not from the menu\n");
                                                                        printf("Please try again.\n\n");
                                                                } 
                                                                break;
                                                        }
                                                }
                                                break;
 
                                        }
 
                                while (selection != 8);
                       
                        }
                        default:
                        {       
                                if (choice != 0)
                                {
                                        printf("\nYour selection was not from the menu\n");
                                        printf("Please try again.\n\n");
                                }
                                break;
                        }
                }
        }
        while (choice != 0);
return (0);
}

---

happy?

Quote:

---

Originally Posted by Salem

400+ lines of unindented code - no thanks!

Here, read this
SourceForge.net: Indentation - cpwiki

---

I would like to add something to this ,which obviously finds me in an agreement.

Friendly tip : You have an error.Everybody has been into a situation like that ;)
So how to help us help you.Post the code that has the error!Not the code that you had before the error.Report what the compiler says.Copy paste the messages he sends to you!

Moreover posting all the code of yours might be not a must. To be more clear, posting your whole code should the last thing to do.
The ideal thing to do is to post as few lines of code as possible to fully describe your problem.
This of course takes some experience, but you have to get yourself thinking like this...
Example
Assume that you are into a situation that your compiler throws an error of undefined variable in a large program..
You want to post , because after trying to solve it yourself multiple times, you didn't succeed it.What you should do?Post the whole code?
No, try to isolate the error .Also post the error message too.

Code:

---

#include <stdio.h>

int main(void)
{
    char buf[10];
    int i;

    printf("Please type an alpharithmetic input\n");
    fgets(bof , 10 , stdin);
    .....
    /* 64387648367 lines of code */
    return 0;
}

---

The error

Code:

---

Macintosh-c8bcc88e5669-9:~ usi$ gcc -Wall px.c -o px
px.c: In function ‘main’:
px.c:9: error: ‘bof’ undeclared (first use in this function)
px.c:9: error: (Each undeclared identifier is reported only once
px.c:9: error: for each function it appears in.)

---

Wasn't it better that i isolated the problematic code from the rest of my huge program? :)
Of course it is not so simple as that every time , but i think you got my point :)

EDIT : We answered the same time.Read my post too and think twice of what you should post :)

Not particularly, you've used some pre-coloured code, and in doing so, suppressed the boards ability to line number the code for you.
Can you do "paste as text" in future.

> printf("\nFIND THE AREA OF A SHAPE\n\n");
FWIW, all of this code should be reduced to

Code:

---

case 8:
{
    doShapeAreas();
    break;
}

---

And all 8 cases which make up the area calculations moved into a new function along the lines of

Code:

---

void doShapeAreas ( void ) {
    do
    {
        printf("\nFIND THE AREA OF A SHAPE\n\n");
        printf("Which shape?\n");
        printf("\t1 - Square\n");
        printf("\t2 - Rectangle\n");
        printf("\t3 - Parallelogram\n");
        printf("\t4 - Trapezoid\n");
        printf("\t5 - Circle\n");
        printf("\t6 - Ellipse\n");
        printf("\t7 - Triangle\n");
        printf("\t8 - Go back to previous menu\n");
           
        printf("\nMake a selection: ");
        scanf("%d", &selection);
                   
        switch (selection)
        {
            case 1: 
        // and so on
    } while ( selection != 8 );
}

---

there is no error and my areas work fine. the only problem was when i tried to use the M_PI in place of my defined PI value, which isn't a big deal anyways. my teacher wants me to write my own code and algorithms and not just use what is included in the math.h header file, there is no problem here. it might be a longer code that i can probably condense but memory is not an issue here.

i would have placed just a few lines of code but you asked to see my code, you did not specify what you wanted to see so i gave it all to you. my main goal from where my code is now, to where i would want it to be is being able to input a string of characters (i.e. 2+5/2*8 + (2-5) ) and be able to solve. the problem i am having with that code is i cant seem to convert from a char* to int or double.

Code:

---

#include<stdio.h>
#include<math.h>
#include <stdlib.h>
#include <string.h>
int indexOf(char input[],char search)
{
        int d;
        int index = -1;
        for(d=0;d<strlen(input) && index==-1;d++)
        {
                if(input[d]==search)
                        index = d;
        }
        return index;
}


int twoVariableExecution(char input[])
{
        int d;
        char operation = '-';
        int operand_index = -1;
        int plus_index = indexOf(input,'+');
        int sub_index = indexOf(input,'-');
        int mul_index = indexOf(input,'*');
        if(plus_index > -1)
        {
                operation = 'A';
                operand_index = plus_index;
        }
        else if(sub_index > -1)
        {
                operation = 'S';
                operand_index = sub_index;
        }
        else if(mul_index > -1)
        {
                operation = 'M';
                operand_index = mul_index;
        }


        char first[operand_index-1];
        memcpy(first,input,operand_index);
        char second[55];
        memcpy(second,input + (operand_index+1),(strlen(input)-operand_index));


        double dbl_second;
        double dbl_first;
        dbl_first = first;
        dbl_second = second;


        printf("first is %e and second is %e", dbl_first, dbl_second);


        switch(operation)
        {
                case 'A':
                        printf("you chose addition jackass");
                        break;
                case 'S':
                        printf("you chose subtraction jackass");
                        break;
                case 'M':
                        break;
        }
        return(1);
}
int main(void){
        char user_input[255];
        printf("Print yoru equation:");
        scanf("%s",user_input);
        printf("\nyour chosen equation was: %d\n",twoVariableExecution(user_input));
        printf("%d",indexOf("........ you",'u'));
        return(0);
}

---

About the char* you said, take a look at the last post here..Read the fgets and atoi part :)

Yes i agree that for your code, using your own defined π is not a problem.However where you have the problem with the M_PI is not at all visible by me, because you did not post the code where you get the relative error :)

Quote:

---

Originally Posted by std10093

About the char* you said, take a look at the last post here..Read the fgets and atoi part :)

Yes i agree that for your code, using your own defined π is not a problem.However where you have the problem with the M_PI is not at all visible by me, because you did not post the code where you get the relative error :)

---

I get the error if i delete #define PI 3.14159 and then anywhere i have used my defined PI i replace with M_PI it tells me that M_PI has not been defined as a variable. (obviously in my area equations for circle and ellipses)

Which means that these functions do not see the definition i would say...If you want to solve it post the code of it :)

is it really that hard just to scroll through my code and see what im talking about?

Code:

---

case 5:                           
{
        printf("\nArea Of A Circle\n");
        printf("\nEnter the radius: ");
        scanf("%lf", &rad1);
        while(rad1 <= 0)
        {
                printf("ERROR!! Distance must be a positive number\n\n");
                printf("Enter the radius: ");
                scanf("%lf", &rad1);
        }
        area = (rad1 * rad1) * PI;
        printf("The area of a circle with a radius of %.4f is %.4f\n\n", rad1, area);
        break;
}
case 6:
{
        printf("\nArea Of An Ellipse");
        printf("\nEnter radius-1: ");
        scanf("%lf", &rad1);
        while(rad1 <= 0)
        {
                printf("ERROR!! Distance must be a positive number\n\n");
                printf("Enter radius-1: ");
                scanf("%lf", &rad1);
        }
        printf("\nEnter radius-2: ");
        scanf("%lf", &rad2);
        while(rad2 <= 0)
        {
                printf("ERROR!! Distance must be a positive number\n\n");
                printf("Enter radius-2: ");
                scanf("%lf", &rad2);
        }
        area = (rad1 * rad2) * PI;
        printf("The area of an ellipse with a radius-1 of %.4f and a radius-2 of %.4f is %.4f", rad1, rad2, area);
        break;
}

---

is the only place i use my pre defined PI, but when i add volumes i will use it more. again, this isn't necessarily a problem though as my code works fine without using the M_PI command

I did scroll down your code :)

M_PI is not a command.It is defined inside the math library.
If you want to use it you have to replace PI with M_PI

Quote:

---

Originally Posted by std10093

I did scroll down your code :)

M_PI is not a command.It is defined inside the math library.
If you want to use it you have to replace PI with M_PI

---

That is what i've been saying.... i have the math.h header file included and the M_PI does not work... i cant explain this any more clear than i already have.

"error #2048: Undeclared identifier 'M_PI'."

What compiler/OS are you using?
Perhaps try adding this line directly above "#include <math.h>"

Code:

---

#define _USE_MATH_DEFINES

---

Quote:

---

Originally Posted by friedsandwich

That is what i've been saying.... i have the math.h header file included and the M_PI does not work... i cant explain this any more clear than i already have.

"error #2048: Undeclared identifier 'M_PI'."

---

how to you compile the program? Do you also include -lm?

I am using Pelles C, I use this because this is the one we use at school.

Quote:

---

Originally Posted by Matticus

What compiler/OS are you using?
Perhaps try adding this line directly above "#include <math.h>"

Code:

---

#define _USE_MATH_DEFINES

---

---

this worked. :)

Maybe on top of the arithmetic your program offers you could add to the functionality with a memory function or 'cancel entry' function in case the user is say adding lots of numbers and makes a mistake with one of the values - you can remove the last one entered

Quote:

---

Originally Posted by rogster001

Maybe on top of the arithmetic your program offers you could add to the functionality with a memory function or 'cancel entry' function in case the user is say adding lots of numbers and makes a mistake with one of the values - you can remove the last one entered

---

hmm... that would be an awesome option, but no idea how to implement that...