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Comparing ArrayList and double array[]

Gabriel White
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Joined: Mar 02, 2003
Posts: 233
Hi all, I have some code...that doesn't work. I am trying to find the common elements in two arrays. One of them is an array list full of doubles and the second is a double array full of doubles. I am trying to display the value of the element that they have in common and the element number that it is in.

Here is my code:

Thanks in advance.

Henry Wong

Joined: Sep 28, 2004
Posts: 20533

Couple of really obvious mistakes in your "if" condition...

- An double value (array2[i]), which is a primative, can't be casted to a string.

- The "if" condition is expecting a boolean value (or expression) -- not a Double object.


Books: Java Threads, 3rd Edition, Jini in a Nutshell, and Java Gems (contributor)
Gabriel White
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Joined: Mar 02, 2003
Posts: 233
Hey Henry, thanks for the reply.

I have since changed my code. I did know about the casting the primitive type, but now I can get it to run, but it is all wrong.

Here is my resulting code looking for an indexOf in the Arraylist.

Stephen Foy
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Joined: Oct 17, 2005
Posts: 143

Stephen Foy - Microsoft Application Development Consultant
Gabriel White
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Joined: Mar 02, 2003
Posts: 233
Thanks Steve, but still double is required on indicated line in code:

Garrett Rowe
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Joined: Jan 17, 2006
Posts: 1296
You could turn your array into a List<Double> using Arrays.asList(), and then call the retainAll() method.

Some problems are so complex that you have to be highly intelligent and well informed just to be undecided about them. - Laurence J. Peter
Gabriel White
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Joined: Mar 02, 2003
Posts: 233
I don't think that my compiler will accept Generics. It says something like requires 1.5, current version 1.2.
Rusty Shackleford
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Joined: Jan 03, 2006
Posts: 490
1.2 is very old(6 or 7 years I think). Is there a reason you are using such an old compiler?
[ April 03, 2006: Message edited by: Rusty Shackleford ]

"Computer science is no more about computers than astronomy is about telescopes" - Edsger Dijkstra
Ken Blair
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Joined: Jul 15, 2003
Posts: 1078
If the compiler knows it requires 1.5 I doubt it's actually that old. Perhaps that's just the default target for their IDE or whatever they're using? @OP: Is there any reason you have to compile code with a 1.2 compliance?
I agree. Here's the link:
subject: Comparing ArrayList and double array[]
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