Programming C, C++, Java, PHP, Ruby, Turing, VB
Computer Science Canada 
Programming C, C++, Java, PHP, Ruby, Turing, VB  

Username:   Password: 
 RegisterRegister   
 Can someone explain this question
Index -> Programming, Java -> Java Help
View previous topic Printable versionDownload TopicSubscribe to this topicPrivate MessagesRefresh page View next topic
Author Message
chromium




PostPosted: Sat Mar 01, 2014 7:51 pm   Post subject: Can someone explain this question

Im not understanding what this questions is asking:
Posted Image, might have been reduced in size. Click Image to view fullscreen.

Please can someone explain it to me. Thanks.
Sponsor
Sponsor
Sponsor
sponsor
Panphobia




PostPosted: Sat Mar 01, 2014 8:13 pm   Post subject: RE:Can someone explain this question

It seems pretty simple, I just solved it. You just need to implement a recursive function that uses that approximation expression. So basically if you know what recursion is, you know you want the function to stop calling itself at some time, so this is your base case, in the question it says exactly when to stop. So
code:

if(TARGET HAS BEEN MET)
     return answer
else
     RECURSIVE CALL
chromium




PostPosted: Sat Mar 01, 2014 8:34 pm   Post subject: Re: RE:Can someone explain this question

Panphobia @ Sat Mar 01, 2014 8:13 pm wrote:
It seems pretty simple, I just solved it. You just need to implement a recursive function that uses that approximation expression. So basically if you know what recursion is, you know you want the function to stop calling itself at some time, so this is your base case, in the question it says exactly when to stop. So
code:

if(TARGET HAS BEEN MET)
     return answer
else
     RECURSIVE CALL


But what am i supposed to be returning? The cube root of 'a'?
Panphobia




PostPosted: Sat Mar 01, 2014 8:39 pm   Post subject: RE:Can someone explain this question

which is t, so yes!
chromium




PostPosted: Sat Mar 01, 2014 8:48 pm   Post subject: Re: RE:Can someone explain this question

Panphobia @ Sat Mar 01, 2014 8:39 pm wrote:
which is t, so yes!

K Ive done this so far:

code:
    public static double betterCubeRoot (double a, double t)
    {
        double tCubed = Math.pow (t, 3);
        double dif = Math.abs (tCubed - a);

        double eq = ((a / (t * t)) + 2 * t) / 3;
       
        if (dif < 0.001)
        {
            return eq;
        }
        else
        {
           
            return betterCubeRoot (eq, t) ;

        }
    }

Im still kind of unsure of what the values of a and t are.
Panphobia




PostPosted: Sat Mar 01, 2014 8:50 pm   Post subject: RE:Can someone explain this question

a is the number you're trying to get the cube of
t is the cube root approximation

so with that out there, looking at your recursive call, is it right?
chromium




PostPosted: Sat Mar 01, 2014 8:52 pm   Post subject: Re: RE:Can someone explain this question

Panphobia @ Sat Mar 01, 2014 8:50 pm wrote:
a is the number you're trying to get the cube of
t is the cube root approximation

so with that out there, looking at your recursive call, is it right?


I dont think so. It isnt correctly returning the cube root of a. What initial value should t have?
Panphobia




PostPosted: Sat Mar 01, 2014 8:58 pm   Post subject: Re: Can someone explain this question

For this to work t can start out as any positive number, but anyway. Look at your logic right now, go through your code and figure out where the problem is. You are passing it a value t in your main function/method, but is t ever changed? Also a is supposed to stay constant since it is the number you are comparing to t^3. Look at your base case too, you are checking if Math.abs(t*t*t-a) < 0.001, so why are you returning eq? the difference was calculating with t, not eq.
Sponsor
Sponsor
Sponsor
sponsor
Insectoid




PostPosted: Sat Mar 01, 2014 9:06 pm   Post subject: RE:Can someone explain this question

Read through the question again, it tells you.
Display posts from previous:   
   Index -> Programming, Java -> Java Help
View previous topic Tell A FriendPrintable versionDownload TopicSubscribe to this topicPrivate MessagesRefresh page View next topic

Page 1 of 1  [ 9 Posts ]
Jump to:   


Style:  
Search: