Hi,
   Basically, below is a simple java script to copy a complete file
and produce an output file containing an exact copy of the original:

import java.io.*;

public class Copy {
    public static void main(String[] args) throws IOException {
File inputFile = new File("clust_2.0_Votes_Candidates_-1.scr");
File outputFile = new File("outagain.txt");

       FileReader in = new FileReader(inputFile);
       FileWriter out = new FileWriter(outputFile);
       int c;

       while ((c = in.read()) != -1)
          out.write(c);

       in.close();
       out.close();
    }
}


But my problem is that I need to 'selectively' copy only certain info
from the file.

E.g,


117 0.920765 (117 118 119 120 121)
109 0.640138 (109 110 111 112 113)
34 0.640138 (34 36)
35 0.640138 (35)
37 0.640138 (37)
97 0.615852 (97)
94 0.615852 (94 95 96)
52 0.615852 (52)
31 0.613872 (31)
76 0.592357 (76 77)
38 0.592357 (38 39)

I only want to copy the numbers on the immediate left. 117, 109, 34,
35, 37 etc and have them reproduced in an output file like this:

117
109
34
35
37
97
94
52
31
76
38

Please help, 
Thanks,
Hook

Hello Hook,

If you want to be able to parse the data in your input file, I suggest
using a BufferedReader. This will allow you to retrieve one line at a
time (rather than one character which you are currently doing). We can
then check for the first space on that line, grab everything before
it, and appending a new line character. Here is the modified code:

import java.io.*;

public class Copy {
    public static void main(String[] args) throws IOException {
File inputFile = new File("clust_2.0_Votes_Candidates_-1.scr");
File outputFile = new File("outagain.txt");

       BufferedReader in = new BufferedReader(new FileReader(inputFile));
       FileWriter out = new FileWriter(outputFile);
       String inData;
       String segment;

       while ((inData = in.readLine()) != null)
       {
          segment = inData.substring(0, inData.indexOf(" ")) + "\n";
          out.write(segment);
       }

       in.close();
       out.close();
    }
}

If you have any problems with the code above please post a
clarification and I will respond promptly.

Cheers,
answerguru-ga

---

Request for Answer Clarification by hook80-ga on 15 Mar 2006 08:27 PST

Hey guru,
          I'm a complete java novice so forgive my ignorance. Is what
you've suggested( "We can then check for the first space on that line,
grab everything before it, and appending a new line character.." )
what you've done? If so it looks good.
Just one thing, i understand up as far as:
FileWriter out = new FileWriter(outputFile);

Could you just explain what each of remaining the lines is doing?

Hook

---

Clarification of Answer by answerguru-ga on 15 Mar 2006 09:10 PST

Yes - what I described is what the code is doing.

The while loop will iterate through the input file until it reaches
the end. At each line, it will find the the part before the first
space and append a newline character to it. This string is then
written to the output file.

Hope that helps :)

answerguru-ga

Thanks alot - really helped me out!

Hook