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**hello**
ive created two vectors parallely ,one for strings and one for floats.Every string corresponds to a float.Thii is done inside a FOR loop. After the loop i calculate the min of floats and i need to get the corresponding string ,but unfortunately i dont get the correct string.
Is my approach wrong,or should i continue experimenting towards this solution?
(I m trying to do this using a hashmap too)
Hello speaker!
Can you post your code?
Please explain what you are doing and show the code that is accessing the two Vectors. If the Vectors are parallel, then an index used with each Vector's get method will return the corresponding elements.Quote:
dont get the correct string.
Is this the same question:
http://www.javaprogrammingforums.com...know-java.html
Why start another post for the same question
yes this is me! i use an index as you say ,but it returns the values only if executed inside the for loop.Quote:
Originally Posted by Norm
Not true.Quote:
returns the values only if executed inside the for loop.
You do not need to use a loop to get elements from a Vector. You can call its methods anywhere in your code.
ok..the loop is done in order to put float values into one vector,and string values to another vector.
after the loop i find easily the min value of the float vector,but i still cant associate it with the correct string.
When you find the index for the float value in one Vector, then use that same index to get the corresponding String from the other Vector.
Code :Vector src =new Vector(); Vector totVector=new Vector(); for (int j = 0; j < energySource.size(); j++) { Item sourceItem = (Item) energySource.elementAt(j); //i get Items from energySource vector if (supply.description.isACover(sourceItem.description)) { if (reasoner.checkCompatibility(supply.description, sourceItem.description)) { .......... } else { ........... } //rTOT1 is a float number rTOT1 = (alfaTOT * rSRC + betaTOT * rSRC) / depthSrc; if (rTOT1 < minScore) { minScore = rTOT1; bestFunct = supply; bestIndex = j; } src.add(sourceItem);//add items to new vector, parallel of totVector totVector.add(rTOT1);//add floats to totVector System.out.println(supply.name + " + " + sourceItem.name + ">>>rTOT1 " + rTOT1); } else { candidati.removeElementAt(j); j--; } } Object rTOT1min = Collections.min(totVector); //find the min of totVector Float bestRank = (float) rTOT1min; //casting?! System.out.println(" Best Rank : " + bestRank ); //printing this minValue
and my problem is that after printing the minValue ,i have to get the sorresponding Item.
how do i get i find the correct index outside the loop?
Can you explain what the problem is with using the same index in two Vectors?
Post the output from your code and explain what is wrong with it.
so,i thought i should add something like this :Quote:
Originally Posted by Norm
Item newItem = (Item) src.elementAt(totVector.indexOf(rTOT1min)) ; <-------inside the parenthesis goes the index ,correct?
System.out.println("source chosen: "+newItem.name);
What happens when you compile and execute that code?
what value does the indexOf() method return? Make a separate statement and print out the value returned.
well it seems to be working like this,but after a number of loops i get an ArrayOutOfBoundsException after a few loops
heres the output
Code :
what value does the indexOf() method return? Make a separate statement and print out the value returned.
hmmmm..it gives me a the min Float number..i thought it would give me an integerQuote:
Originally Posted by Norm
Can you show what was printed out. And the code that was used.
What indexOf() method are you using. Most versions of that method return an int value.
ok im sorry im panicking here..i get an integer which denotes the index
You need to add some printlns to debug what the code is doing to get the exception. Print out the value of the float number and the value returned by the indexOf() method just before the statement that causes the error.
Quote:
Originally Posted by Norm
Code :
What is the size of the Vector at line 290?
Is 29 the value returned by the indexOf() method?
What object was the indexOf() method searching the Vector for?
Where is the first line of the stack trace that shows the type of error?
this is the line: newItem=(Item) src.elementAt(totVector.indexOf(rTOT1min));Quote:
Originally Posted by Norm
yes it returns that value.it shouldnt.Quote:
Is 29 the value returned by the indexOf() method?
hmmm....it suppose to find the corresponding Item for the minValue(float)Quote:
What object was the indexOf() method searching the Vector for?
Did you print out the value that indexOf was searching for?
What is the size of the Vector when the error occurred? Can you print it out?
Where is the first line of the stack trace from the error. Your posted output does not show it.
You need to print out all these values so you can see what the computer sees when it executes the code where the error occurs.
that was very helpful. i realised that one of the vectors had always 6 elements ,while the other was incremented by 6 after every loop[duh!]
So i clear the problematic vector after every loop:
totVector.clear();
this seems to work.:-)
thnk you very much and forgive me for my ignorance.
The output from println can help you see what the computer sees. I find it very useful.