read in data, manipulate, and print back out

This is a discussion on read in data, manipulate, and print back out within the C Programming forums, part of the General Programming Boards category; Hi, I have some data in the form 1 2 3 4 5 6 7 8 9 in a txt ...

  1. #1
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    read in data, manipulate, and print back out

    Hi,

    I have some data in the form

    1 2 3
    4 5 6
    7 8 9

    in a txt file.

    How would I go about converting it into a list like:
    1
    2
    3
    4
    5
    6
    ...etc.

    and printing that to another txt file?

    Thanks!!

  2. #2
    MTK
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    Maybe something like this:

    1. Read the file to a string
    2. Replace any consecutive groups of 1 or more whitespace chars with a single '\n'
    3. Write the string to a file


    This may help you with file I/O (don't pay attention that is says C++ Reference):

    cstdio (stdio.h) - C++ Reference

  3. #3
    Registered User C_ntua's Avatar
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    Even more simple:
    1. Create output file
    2. Read a character from input file
    3. If it is a <space> right a <newline> character in you output file. Otherwise write the character to your output file as it is
    4. Repeat step 2, 3 until EOF

    This should just take a few lines of code

  4. #4
    MTK
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    That does seem more efficient.

  5. #5
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    You probably don't want to do this, at all - how's *that* for efficiency?

    Nobody (probably) cares how the data is arranged on the drive, unless it's part of a struct or record, which this is not. All they want is to view the data, like:

    1
    2
    3
    etc.

    So:

    Code:
    fscanf(ptrFile,"%d %d %d", &num1, &num2, &num3);
    printf("%d\n%d\n%d\n, num1, num2, num3);

  6. #6
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    Hi,

    Read in the data from the original text file and the replace all the character ' ' with '\n'.
    Then put it in another file. That's it!

    Carle
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  7. #7
    ATH0 quzah's Avatar
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    Why are you just going through threads and repeating everything everyone else has already said?


    Quzah.
    Hope is the first step on the road to disappointment.

  8. #8
    Guest Sebastiani's Avatar
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    ...not to mention threads old enough to be effectively dead...

  9. #9
    and the Hat of Guessing tabstop's Avatar
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    Quote Originally Posted by quzah View Post
    Why are you just going through threads and repeating everything everyone else has already said?


    Quzah.
    I'm sure it couldn't possibly have anything to do with the link in his signature.

  10. #10
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    MTK how would one go about doing your second step
    Replace any consecutive groups of 1 or more whitespace chars with a single '\n'
    Im having issues with that on my program, but i need it for more than just whitespace, I need more than one whitespace to be combined with commas tabs, etc to return only one '\n'

  11. #11
    ATH0 quzah's Avatar
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    Code:
    while( (c = fgetc( somefile ) != EOF )
    {
        if( isdigit( c ) )
        {
            ...do whatever for digits...
        }
        else
        if( isspace( c ) )
        {
            while( (c = fgetc( somefile )) != EOF && isspace( c ) ) ;
            ...do whatever to output your newline...
        }
        else
        {
            ...do whatever for nonspace nondigit characters...
        }
    
    }
    Quzah.
    Hope is the first step on the road to disappointment.

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