Matrix in a file. Help!

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  1. #1
    Registered User Arminel's Avatar
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    Matrix in a file. Help!

    I write a matrix in a text file as it shows the example:

    2 5 2 5 6
    2 3 4 6 3
    2 5 6 8 6

    I want to find out the number of lines and columns. I've started writing the code but I can't determine the number of lines.
    Code:
    #include <stdio.h>
    
    int main()
    
    {
    FILE *f;
    f = fopen ("mat1.txt", "r");
    int spaces=0, endl=0;
    char c, d;
    do {
          fscanf(f, "%c", &c);
          if ( c == ' ' )
              spaces++;
         }
    while ( c != '\n' );
    fseek ( f, 0, SEEK_SET );
    do {
          fscanf(f, "%c", &d);
          if ( d == '\n' )
              endl++;
         }
    while (!EOF);
    printf("The matrix has %d columns and %d lines.", spaces+1, endl+1);
    fclose(f);
    return 0;
    }
    What did I do wrong ?

  2. #2
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    Well what's the output?

  3. #3
    ZuK
    ZuK is offline
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    Code:
    while (!EOF);
    EOF is a constant. !EOF is the same as
    Code:
    while (0);
    Kurt
    Last edited by ZuK; 12-24-2006 at 05:34 AM.

  4. #4
    Registered User Arminel's Avatar
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    The matrix has 5 columns and 1 lines.
    This output is for the example I gave.

  5. #5
    and the hat of wrongness Salem's Avatar
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    Both your file reading loops need to be of this form

    Code:
    while ( fscanf(f, "%c", &c) != EOF ) {
      // do something with c
    }
    In the first loop, you could do this to get out of the loop when you see the first newline
    if ( c == '\n' ) break;
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.
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  6. #6
    Registered User ssharish2005's Avatar
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    user fgets() function to find out the number of lines.
    Code:
        while(fgets(str,80,fp) != NULL)
            line++;
    this gives you the number of lines which u have read. By keeping tack of line variable

    to find out the num of col it depends on the way each file is stored

    example: if your line is stored with out the space like
    Code:
    12345
    just count the num of char in a line. or if you have like this
    Code:
    1 2 3 4 5
    use this tokenize the string

    ssharish2005

  7. #7
    Registered User Arminel's Avatar
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    Thanks! Work fine now

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