How to pass a matrix/array from main to a function

This is a discussion on How to pass a matrix/array from main to a function within the C Programming forums, part of the General Programming Boards category; Hello, http://codeviewer.org/view/code:a70 As you can see i have a bunch of matrix and an array in my main function and ...

  1. #1
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    How to pass a matrix/array from main to a function

    Hello,
    http://codeviewer.org/view/code:a70
    As you can see i have a bunch of matrix and an array in my main function and i have a bunch of other functions listed above. I'm trying to pass the matrix and array to those other functions and in those functions do some checks and edit the values of those matrix and array that are in the main. I don't think im suppose to return, am i passing them correctly?


    so....
    declare matrix/arrays in main
    pass them to functions
    do some checks
    if it checks out the condition, edit the values of those matrix and array in the function that i passed them to(to do so i would have to pass them? if so how)

  2. #2
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    use the name of the array:


    Code:
    /*Just a tutorial for a Cboard poster right now.
    
    status: na
    */
    
    #include <stdio.h>
    
    #define SIZEofArray 12
    
    void myFunction(char array[], int);
    
    int main(void) {
      int i, shift;
      char array[12] = { "Is this OK?" };
    
      putchar('\n');
      for(i = 0; i < SIZEofArray; i++)
        printf("%c", array[i]);
    
      printf("\n\n How many letters should I shift upward? [0-26]: ");
      scanf("%d", &shift);
    
      myFunction(array, shift);
      putchar('\n');
    
      for(i = 0; i < SIZEofArray; i++)
        printf("%c", array[i]);
    
      printf("\n\n\t\t\t     press enter when ready");
      while((i = getchar()) != '\n');
      i = getchar();
    
      return 0;
    }
    void myFunction(char array[], int myShift) {
      int i;
      for(i = 0; i < SIZEofArray; i++)
        if(array[i] >= 'A')
          array[i] += myShift;
    
    
    }
    Last edited by Adak; 12-09-2009 at 05:57 PM.

  3. #3
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    I'm not following.

    So i just have to declare the functions at the top "void myFunction(char array[]);"
    Also i noticed in function, the parameters or whatever you want to call them, you don't specify the elements(0-11)/space of the array [12] void myFunction(char array[]), is that suppose to be left without numbers?
    Last edited by Inukami; 12-09-2009 at 05:54 PM.

  4. #4
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    The last dimension is OK to leave blank. All others should be filled in. This is not the only way to pass an array, but it is the simplest and best to use - especially for beginners.

    I edited my earlier post. Try running that program, and see if it start to make sense for you.

    Note that the array values, are changed, in myFunction().


    Yeah, we're *REALLY* fond of calling the parameters, parameters -

  5. #5
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    w-t-f

    26 errors...

    I get a lot of these errors:
    Size of the type 'int[]' is unknown or zero
    what does that mean, im guessing its because i didn't set a value in the function for the arrays
    http://codeviewer.org/view/code:a72


    arrr so frustrating..

    C:\Borland\BCC55\Bin>bcc32 ProjectGame.c
    Borland C++ 5.5.1 for Win32 Copyright (c) 1993, 2000 Borland
    ProjectGame.c:
    Error E2453 ProjectGame.c 3: Size of the type 'int[]' is unknown or zero
    Error E2453 ProjectGame.c 12: Size of the type 'int[]' is unknown or zero in fun
    ction TotalScore
    Error E2453 ProjectGame.c 12: Size of the type 'int[]' is unknown or zero in fun
    ction TotalScore
    Error E2453 ProjectGame.c 12: Size of the type 'int[]' is unknown or zero in fun
    ction TotalScore
    Error E2453 ProjectGame.c 14: Size of the type 'int[]' is unknown or zero in fun
    ction TotalScore
    Error E2453 ProjectGame.c 14: Size of the type 'int[]' is unknown or zero in fun
    ction TotalScore
    Error E2453 ProjectGame.c 14: Size of the type 'int[]' is unknown or zero in fun
    ction TotalScore
    Error E2453 ProjectGame.c 16: Size of the type 'int[]' is unknown or zero in fun
    ction TotalScore
    Error E2453 ProjectGame.c 16: Size of the type 'int[]' is unknown or zero in fun
    ction TotalScore
    Error E2453 ProjectGame.c 16: Size of the type 'int[]' is unknown or zero in fun
    ction TotalScore
    Error E2453 ProjectGame.c 23: Size of the type 'int[]' is unknown or zero
    Error E2453 ProjectGame.c 23: Size of the type 'int[]' is unknown or zero
    Error E2453 ProjectGame.c 30: Size of the type 'int[]' is unknown or zero in fun
    ction WinTieLoss
    Error E2453 ProjectGame.c 30: Size of the type 'int[]' is unknown or zero in fun
    ction WinTieLoss
    Error E2453 ProjectGame.c 32: Size of the type 'int[]' is unknown or zero in fun
    ction WinTieLoss
    Error E2453 ProjectGame.c 32: Size of the type 'int[]' is unknown or zero in fun
    ction WinTieLoss
    Error E2453 ProjectGame.c 33: Size of the type 'int[]' is unknown or zero in fun
    ction WinTieLoss
    Error E2453 ProjectGame.c 33: Size of the type 'int[]' is unknown or zero in fun
    ction WinTieLoss
    Error E2453 ProjectGame.c 35: Size of the type 'int[]' is unknown or zero in fun
    ction WinTieLoss
    Error E2453 ProjectGame.c 35: Size of the type 'int[]' is unknown or zero in fun
    ction WinTieLoss
    Error E2453 ProjectGame.c 37: Size of the type 'int[]' is unknown or zero in fun
    ction WinTieLoss
    Error E2453 ProjectGame.c 37: Size of the type 'int[]' is unknown or zero in fun
    ction WinTieLoss
    Error E2453 ProjectGame.c 38: Size of the type 'int[]' is unknown or zero in fun
    ction WinTieLoss
    Error E2453 ProjectGame.c 38: Size of the type 'int[]' is unknown or zero in fun
    ction WinTieLoss
    Error E2453 ProjectGame.c 42: Size of the type 'int[]' is unknown or zero in fun
    ction WinTieLoss
    Error E2228 ProjectGame.c 42: Too many error or warning messages in function Win
    TieLoss
    *** 26 errors in Compile ***

    C:\Borland\BCC55\Bin>


    EDIT: OKAY so this seemed to have fixed all the errors and it actually ran soo... not sure >_>
    http://codeviewer.org/view/code:a73

    I just have to finish the "DISPLAY()" function to display all the arrays and matrix now.... >_<
    Last edited by Inukami; 12-09-2009 at 07:12 PM.

  6. #6
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    You have to declare the size of all other dimensions, except the last one. This doesn't have that:

    Code:
    #
    void WinTieLoss(int Teams[][], int WinTieLossRecord[][])
    That code viewer has the WORST font and colors.

  7. #7
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    haha which one do you use? Also can you explain why i dont have to declare the last dimensions?

  8. #8
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    I use whatever the forum chooses. I'm not sure what it is, but it's almost square in dimension, so it's good when you use the code tags.

    That codeviewer admin seems like he's trying to play a joke with that font and color combo's!

    The array has to keep the size of the last dimension, internally. So, you're off the hook with that dimension.

    There are other ways to pass arrays, and you don't need to give any dimensional info at all - but that's not really using an array - you're then using raw memory and pointers. The code for that type of data handling, won't win any beauty contests, either.

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