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Thread: selecting even numbers from an array

  1. #1
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    Default selecting even numbers from an array

    Hello,

    I'm stuck with my assignment again which is to:

    1. Read in all 20 lines of text from a file and store them.
    2. Display all the 20 lines of text on the screen
    3. Display every other line in upper case (so the first, then the third etc), you donít need to display the other line at all (i.e. no output of second, fourth etc.)
    4. Display the number of characters in each line of text and display the average of the characters for all 20 lines of text.
    5. Display the first 10 characters from each line of text

    After solving steps 1 and 2 i soon found myself hitting a brick wall again with step 3, everything i've looked at on the net just seems to be to complicated for what i need to do with this step.

    The code I have so far is:
    /** assignment one reading from a file. */
     
    import java.util.Scanner;
    import java.io.File;
     
    class alice{
     
    	public static void main (String args[]) throws Exception
    	{
     
     
    		File myFile = new File("alice.txt");
    		Scanner Scan = new Scanner(myFile);
    		String []aliceline=new String[20];
    		String uppercase;
     
    		for (int line=0;line<20; line++)
     
     
    		{aliceline[line] = Scan.nextLine();
     
     
     
    		System.out.println(aliceline[line]);
     
     
    	}
     
     
    	{
    		uppercase = aliceline; /** i need this part to read all the even lines from the array*/
     
    		System.out.println(uppercase);
    	}
    		Scan.close();
     
    	}
    }

    I have tried lots of things such as uppercase=aliceline[0][2] or [0+2] but it just won't work and i'm now at a loss.
    If anone could please help me with this........


  2. #2
    mmm.. coffee JavaPF's Avatar
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    Default Re: selecting even numbers from an array

    This will help you move forward. It's more simple than you think

    /** assignment one reading from a file. */
     
    import java.util.Scanner;
    import java.io.File;
     
    class alice {
     
    	public static void main(String args[]) throws Exception {
     
    		File myFile = new File("alice.txt");
    		Scanner Scan = new Scanner(myFile);
    		String[] aliceline = new String[20];
    		String uppercase;
     
    		for (int line = 0; line < 20; line++)
    		{
    			aliceline[line] = Scan.nextLine();
    			System.out.println(aliceline[line]);
    		}
     
    		System.out.println("");
     
    		for (int a = 0; a < 20; a++){
    			System.out.println(aliceline[a].toUpperCase());
    			a = a+1;
    		}
     
    		Scan.close();
    	}
    }
    Please use [highlight=Java] code [/highlight] tags when posting your code.
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  3. The Following User Says Thank You to JavaPF For This Useful Post:

    Tate (November 28th, 2010)

  4. #3
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    Default Re: selecting even numbers from an array

    Thankyou so much for your help now i just need to figure out the next steps.

  5. #4
    mmm.. coffee JavaPF's Avatar
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    Default Re: selecting even numbers from an array

    Related Thread - Stuck again

    I may merge these.
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  6. #5
    mmm.. coffee JavaPF's Avatar
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    Default Re: selecting even numbers from an array

    Quote Originally Posted by Tate View Post
    Thankyou so much for your help now i just need to figure out the next steps.
    No problem.

    Try to move forward and show us the code you have done..
    We will help when you get stuck.
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  7. #6
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    Default Re: selecting even numbers from an array

    Hello,

    I'm now stuck with task 4 i've got as far as to display the number of letters in each line but can't quite figgure out how to display the average of the characters for all 20 lines.

    The code I have now is:

     
    /** assignment one reading 20 lines from a file. */
     
    import java.util.Scanner;
    import java.io.File;
     
    class alice{
     
        public static void main (String args[]) throws Exception
        {
     
     
            File myFile = new File("alice.txt");
            Scanner Scan = new Scanner(myFile);
            String []aliceline=new String[20];
            String uppercase;
     
            for (int line=0;line<20; line++)
     
     
            {aliceline[line] = Scan.nextLine();
     
     
     
            System.out.println(aliceline[line]);
     
     
        }
     
     
        System.out.println("");
     
        for (int odd = 0; odd < 20; odd++){
            System.out.println(aliceline[odd].toUpperCase());
                    odd = odd+1;
     
        }
     
        System.out.println("");
     
            for (int b = 0; b < 20; b++)
            {
     
     
                System.out.println(aliceline[b].length());
                System.out.println(); /** I need to work the average in this part of the code */
     
            }
            Scan.close();
     
        }
    }
    Any help with this will be much appriciated I tried following what someone had put on my other post but i'm affraid that i still seem to be getting no where

  8. #7
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    Default Re: selecting even numbers from an array

    Use a for-loop to sum up the length of the 20 lines, then divide by 20 to get an average. Bonus hint: use doubles/floats in order to accurately compute the average (otherwise it will be truncated to the nearest integer).

  9. #8
    mmm.. coffee JavaPF's Avatar
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    Default Re: selecting even numbers from an array

    Take a look at this thread - how do i make my program to do......

    Seeing as your questions are identical, I take it you are in the same class?

    Please be aware that it looks like your University are monitoring these threads.

    Quote Originally Posted by MelanieC View Post
    Hi its Melanie, sounds like your assignment is not going to well!! Just to let you know, you may wish to take a look at the Academic offences, located on myBu. I have advised Nan (who will be marking the work this week) that any work that is believed to be plagarised, will be marked as 0 with a disiplinary with Ruth.
    Just a heads up!
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