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Making a .dat file

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Join Date: Mar 2005

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mb1

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Making a .dat file

Nov 1st, 2005

I need to write a program, in C++, that will read from a .dat file

How do I make one? My book mentions a header line, etc. It does not go into any more detail and I can't find a description of how to do it online.

Am I making this harder than I need to?

Thanks,
MB1

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Re: Making a .dat file

Nov 1st, 2005

Show us your basic attempt start to the code with [code][/code] tags.

"One of the methods used by statists to destroy capitalism consists in establishing controls that tie a given industry hand and foot, making it unable to solve its problems, then declaring that freedom has failed and stronger controls are necessary." --Ayn Rand

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mb1

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Re: Making a .dat file

Nov 1st, 2005

All I can figure is to make a .txt file and call it Scores.dat

In the file:

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
Names       Score1     Score2     Score3      Score4      Score5
Sims          91         89         73          81          93
Names       Score1     Score2     Score3      Score4      Score5
Sims          91         89         73          81          93

I'm supposed to read from the .dat file and compute the scores and assign a letter grade. I've got the program but I have no idea on where to start to make a .dat file.
Thanks for getting back with me.

Last edited by mb1; Nov 1st, 2005 at 4:05 pm. Reason: Arrange information

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Re: Making a .dat file

Nov 1st, 2005

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I've got the program

You've got a program that reads from the .dat file, so why not post that?

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program but I have no idea on where to start to make a .dat file.

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All I can figure is to make a .txt file and call it Scores.dat

I'm confused. As far as I know, a .dat file is just the same as any other text file. It just a name. Or do you draw a distinction?

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mb1

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Re: Making a .dat file

Nov 1st, 2005

I though there was a distinction. I assume I just write the headings with the appropriate information under the headings.

I didn't write the C++ code because I wrote it to read an array. I was confused with the .dat issue.

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Re: Making a .dat file

Nov 3rd, 2005

Yes a .dat is just a different file extention. You can create this in windows with just notepad and when you save it make it filename.dat. Actually, in Linix/Unix it is the same. Just save it with filename.dat.

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Re: Making a .dat file

Nov 3rd, 2005

Its been my experience that .dat files contain binary data, such as the computer's binary representation of an integer and not the ascii digits that you will find in a text file. .dat files normally can not be easily read by text editors such as Notepad.exe.
Exemple:

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
struct mystruct
{
   int a;
   long b;
   float c;
   double d;
};
 
int main()
{
    myruct s 
 
   // write the structure to the file
   ofstream out("mydata.dat", ios::binary);
   out.write((char *)&s,sizeof(s));
   out.close();
 
   // now read the file
   ifstream in("mydata.dat", ios::binary);
   in.read((char*)&s,sizeof(s));
   in.close();
}
struct mystruct
{
   int a;
   long b;
   float c;
   double d;
};

int main()
{
    myruct s 

   // write the structure to the file
   ofstream out("mydata.dat", ios::binary);
   out.write((char *)&s,sizeof(s));
   out.close();

   // now read the file
   ifstream in("mydata.dat", ios::binary);
   in.read((char*)&s,sizeof(s));
   in.close();
}