Importing File to Array

This is a discussion on Importing File to Array within the C Programming forums, part of the General Programming Boards category; So I'm trying to inport a file into an array. The file is of known size, containing 9 numbers (ie ...

  1. #1
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    Importing File to Array

    So I'm trying to inport a file into an array. The file is of known size, containing 9 numbers (ie a 3x3 matrix) separated by spaces and new lines. I need to take this file, and turn it into an array. So far, I have the matrix.dat that looks like:
    Code:
    4 -5 3
    6 -9 3
    4 8 -1
    and I'm trying to import this using nestled for loops like:#
    Code:
    input = fopen("matrix.dat", "r");
    if(input == (FILE*) NULL)
    {
    	printf("Can not open file matrix.dat\n");
    	exit(EXIT_FAILURE);
    }
    else
    {
    	for(i=0; i<3; i++)
    	{
    		for(j=0; j<3; j++)
    		{
    			fscanf(input, "%f", &matrix[i][j]);
    		}
    	}
    	printf("%s", matrix);
    }
    exit(EXIT_SUCCESS);
    Now i'm assuming one of two parts is the problem. Either my for loops are inproperly set up, or (as I am assuming) the 'fscanf' is wrong. The problem is, I'm not sure how to fscanf for multiple dimensional arrays. Any help?

    Cheers
    Last edited by tomeatworld; 11-21-2010 at 09:42 AM.

  2. #2
    C++ Witch laserlight's Avatar
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    How does it not work?
    Quote Originally Posted by Bjarne Stroustrup (2000-10-14)
    I get maybe two dozen requests for help with some sort of programming or design problem every day. Most have more sense than to send me hundreds of lines of code. If they do, I ask them to find the smallest example that exhibits the problem and send me that. Mostly, they then find the error themselves. "Finding the smallest program that demonstrates the error" is a powerful debugging tool.
    Look up a C++ Reference and learn How To Ask Questions The Smart Way

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    I get a seg fault when run!

  4. #4
    C++ Witch laserlight's Avatar
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    How did you declare the matrix 2D array?
    Quote Originally Posted by Bjarne Stroustrup (2000-10-14)
    I get maybe two dozen requests for help with some sort of programming or design problem every day. Most have more sense than to send me hundreds of lines of code. If they do, I ask them to find the smallest example that exhibits the problem and send me that. Mostly, they then find the error themselves. "Finding the smallest program that demonstrates the error" is a powerful debugging tool.
    Look up a C++ Reference and learn How To Ask Questions The Smart Way

  5. #5
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    I've managed to fix it. I'd defined my matrix with dimensions i and j which meant it didn't have enough memory (i think). I've got it working now! Thanks anyway!

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