Loading data into an array from a text file

Question

I'm really struggling with a piece of work, I need to load data from a text file into an array, I have managed to load the data into java and print it, but now the data needs to be split and passed to another class. I tried using .split(" ") but the data doesn't share a common amount of white space so I end up with a huge array half of which is filled with entries that have 2 lots of data or just a white space. Here is the code I have so far:

import java.io.*;

public class Reader {

    int i= 0;
    int k=0;
    static String test;

    public static void main(String[] Args){ 

    String file ="1RainfallSample.txt";        

    //reading   
    try{
        InputStream ips=new FileInputStream(file); 
        InputStreamReader ipsr=new InputStreamReader(ips);
        BufferedReader br=new BufferedReader(ipsr);
        String line;
        while ((line=br.readLine())!=null){
        test+=line+"\n";
        }
        br.close(); 

    }       
    catch (Exception e){
        System.out.println(e.toString());
    } 

    // split(String Delimiter)
    String[] dataArray=test.split("\\s");
    System.out.println("Array :"+dataArray.length);
    for(int i=0;i<dataArray.length;i++)
    {
        System.out.println("array"+i+"  :"+dataArray[i]);
    } 

    }
}

And below is a small example of the data because I don't think I explained it very well.

4   6.10   1.80   1.00  26.10   9.60   0.00   0.00   0.00 

0.00   0.00   3.10   0.30   0.20   0.40  0.00   0.00   0.00   0.00   0.00   0.00   

0.00   2.50   0.00   0.00   0.00   0.00   0.00   0.00   0.00   0.00 -99.992011

I feel like I'm approaching it all the wrong way, I'm not a good programmer as you can tell, just a nudge in the right direction would be appreciated.

first change test+=line+" " cause u want space for delimeter .and u can use regex inside split . for spaces .split("\s+") it will use spaces as split — qwr
– qwr, Commented May 11, 2013 at 16:32

Keppil · Accepted Answer · 2013-05-11 16:31:21Z

2

You can use

String[] dataArray = test.split("\\s+");

to get rid of extra white spaces.

answered May 11, 2013 at 16:31

Keppil

46.3k9 gold badges101 silver badges121 bronze badges

Sign up to request clarification or add additional context in comments.

5 Comments

Farrell Coleman Over a year ago

Holy crap you guys answer questions fast!

Keppil Over a year ago

:) Programmers have way too much free time.

Farrell Coleman Over a year ago

Haha well ty to both of you, that worked a treat I now have an array of 760 ish entries instead of 3000 ish, now to work out how to pass this data to the days class :p. Thanks a lot.

Farrell Coleman Over a year ago

One follow up question i'd ask is how do I then convert the string array into a float, "public float[] (String dataArray[i]);" I tried putting this in the for loop, but to no avail :\

Keppil Over a year ago

@EarlLemongrab: You can declare a float[] floatArray = new float[dataArray.length] and use floatArray[i] = Float.valueOf(dataArray[i]).

ridoy · Accepted Answer · 2013-05-11 17:36:23Z

1

Alternatively if you want to tidy your data, you could match duplicate spaces and remove them or replace with a single space.

First make sure your text is in a string variable, then:

Val = Val.replaceAll(" {2,}", " ");

edited May 11, 2013 at 17:36

ridoy

6,3722 gold badges32 silver badges60 bronze badges

answered May 11, 2013 at 16:42

Karl M.W.

7475 silver badges19 bronze badges

1 Comment

Karl M.W. Over a year ago

Thanks @ridoy. I couldn't figure out how to mark code blocks on the mobile app.

Collectives™ on Stack Overflow

Loading data into an array from a text file

2 Answers 2

5 Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

5 Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related