# computer science lab tips

Discussion in 'OT Technology' started by nur23, Feb 12, 2007.

1. ### nur23OT Supporter

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For my computer science labe are required to convert from hexidecimal (base 16) to base 2.

Can someone help me by telling me how i should begin? I sure it starts with some kind of loop, but from then on i'm stumped.

Code:
```// Lab16st.java
// The Number System Converter
// Student Version

import java.util.Scanner;
public class Lab16st
{
public static void main (String args[])
{
System.out.println("Lab 16 - Number Conversion Program\n\n");

// The next 2 lines are used in all versions.
System.out.println("ABCD1234 Base-16 converts to " + BaseConverter.fromHexToBin("ABCD1234") + " in Base-2.\n");
System.out.println("E12B47F5 Base-16 converts to " + BaseConverter.fromHexToBin("E12B47F5") + " in Base-2.\n");

// The next 2 lines are used in the 90-point versions and above.
// System.out.println("1011111011101111 Base-2 converts to " + BaseConverter.fromBinToDec("1011111011101111") + " in Base-10.\n");
// System.out.println("11100100100110110 Base-2 converts to " + BaseConverter.fromBinToDec("11100100100110110") + " in Base-10.\n");
// The next line is used in the 95-point versions and above.
// System.out.println("1011111011101111 Base-2 converts to " + BaseConverter.fromBinToHex("1011111011101111") + " in Base-16.\n");
// The next line is used in the 100-point versions and above.
// System.out.println("11100100100110110 Base-2 converts to " + BaseConverter.fromBinToHex("11100100100110110") + " in Base-16.\n");

// The next 3 lines are used in the 105 and 110-point versions.
// System.out.println("1000 Base-10 converts to " + BaseConverter.fromDecToAny(1000,5) + " in Base-5.\n");
// System.out.println("1000 Base-10 converts to " + BaseConverter.fromDecToAny(1000,8) + " in Base-8.\n");
// System.out.println("200 Base-10 converts to " + BaseConverter.fromDecToAny(200,2) + " in Base-2.\n");

// This last line is only used in the 110 point version.
// System.out.println("48879 Base-10 converts to " + BaseConverter.fromDecToAny(48879,16) + " in Base-16.\n");
}
}

class BaseConverter
{
public static String fromHexToBin(String hexNum)
{
String binNum = "";

return binNum;
}
```

2. ### deusexaetheraOT Supporter

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We don't do homework here.

That said, you can convert from base 16 to base 2 by separating each digit and multiplying it by the appropriate power of 16^x, adding all of the products together, then dividing by powers of 2^x to extract the binary digits.

3. ### CyberBulletsI reach to the sky, and call out your name. If I c

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4. ### nur23OT Supporter

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I'm not asking you to do my homework. What i am asking is for some help since i don't know how to start.

You could at least offer some help.

To cyber: Google is very inaccurate in terms of finding java coding that must fit the specific requirements of this lab. If there is such a website that offers the help i'm siking, i would gladly follow any links you guys post.

5. ### deusexaetheraOT Supporter

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I did offer some help. I told you the algorithm you need to implement in order to convert hex to binary; in effect, I did the hard part for you.

6. ### nur23OT Supporter

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I understand what you said, yet it will be if no use if i can't put it in terms of coding.

Will the conversion be sent through a loop? Also, how do i convert characters into integer form, that will be expressed in a base 2 format?

7. ### CoottieBOOMER......SOONEROT Supporter

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So you can't google like this:
java convert char to int

Ok...I'll try it...let's see what we get:
hmmm...very first link
http://forum.java.sun.com/thread.jspa?threadID=571418&messageID=2828674

Dude google is not unreliable...you simply need to learn to search

8. ### GOGZILLADouble-Uranium Member

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youre not a CS major are you?

9. ### Sexual VanillaNew Member

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I would hope not.

10. ### CorpOT Supporter

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please drop out now

11. ### GOGZILLADouble-Uranium Member

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yeah i was gonna say go ahead and drop the course and change majors if you are CS/CE but if you're like an IT major or something you could just grind this one course out.

12. ### deusexaetheraOT Supporter

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If you can't translate English into Java -- even with all of the guides to Java programming and keywords available online -- that's your problem. I told you what you need to do, I'd even be willing to spot-check your code if you can't get it to compile, but I'm not going to do the whole damn thing for you.

It's doubtful that there is a pre-built Hex->Bin function available in the Java STL (or whatever Java calls its STL), because if there were then your professor wouldn't have used it as an assignment. You're just going to have to come up with your own way of storing the input and output; as far as displaying the binary numbers is concerned, you'd be best off to store the output in a text string instead of a number, so you can make it display exactly the way you want.