Read a 2D array

This is a discussion on Read a 2D array within the C Programming forums, part of the General Programming Boards category; I need to make a matrix[i][j] in C which will read from a file with the format bellow: 1,3.567,4.893,1.756 2,7.875,8.872,4.438 ...

  1. #1
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    Read a 2D array

    I need to make a matrix[i][j] in C which will read from a file with the format bellow:

    1,3.567,4.893,1.756
    2,7.875,8.872,4.438
    3,8.234,9.987,3.908
    .
    .
    .

    so as the matrix[0][0]=1, matrix[0][2]=4.893, matrix[2][1]=8.234 and so on ...

    can anyone help me in how to allocate memory and read the file

    Thanks

  2. #2
    Kernel hacker
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    Do you KNOW that you always have three columns?

    If so, you could use realloc on a float/double [3] array.

    --
    Mats
    Compilers can produce warnings - make the compiler programmers happy: Use them!
    Please don't PM me for help - and no, I don't do help over instant messengers.

  3. #3
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    The num of rows and columns will be different

  4. #4
    Kernel hacker
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    Then you need some way of determining how many columns there are, and use a 2D dynamic array - common question here, so search the forum for an answer. It's certainly a lot easier to solve this sort of problem if you know a max size that it may be, but I also understand that this is not always feasible.

    --
    Mats
    Compilers can produce warnings - make the compiler programmers happy: Use them!
    Please don't PM me for help - and no, I don't do help over instant messengers.

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