Array initialization

Question

I have a 3-D array [8][8][1002], which remains static with every run(values don't change). Each page of array contains binary combination (8x8 matrix).

The array will take a lot of time to load, which I want to avoid.

Any way to reduce the time taken?

Or any other data structure may work effectively faster?

UPDATE:

The initialization of array is done by exhaustive method :

Loop1 for i:
  Loop2 for j:
   Loop3 for k:
   array[i][j][k]=1 //or 0 some logic

By loading, I mean array initialization.

If you don't want it to take any time then initialize it with immediate values. This makes your code larger (much), but eliminates the issue you're discussing. You can use a simple code generator to output the init code. Loading it from a file might be faster as well, you could serialize it. — Dave Newton
– Dave Newton, Commented Feb 6, 2014 at 14:59
Then I can bet a cookie that your real bottleneck is not in the array loading :). I recommend you to use a profiler for your application like VisualVM that already comes since JDK 6. If you're using JDK 7 u 40, you can use Java Mission Control, which comes with this and later distributions. — Luiggi Mendoza
– Luiggi Mendoza, Commented Feb 6, 2014 at 15:40

Ashot Karakhanyan · Accepted Answer · 2014-02-06 15:07:17Z

1

If you want to initialize with 0, so you don't need to write any init code, before default value is 0 when you creating an instance of array:

final int[][][] array = new int[1][1][1];
System.out.println(array[0][0][0]);

The result is: 0

answered Feb 6, 2014 at 15:07

Ashot Karakhanyan

2,8283 gold badges26 silver badges29 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

joey rohan Over a year ago

Hmm interesting, so have to work only on selective ones.

Dave Newton · Accepted Answer · 2014-02-06 15:19:14Z

0

If speed is a must, try declaring the array as final, and initialize it while you create it. That'll take a lot of code but will probably be faster.

final int[][][] array = {...}

edited Feb 6, 2014 at 15:19

Dave Newton

161k27 gold badges263 silver badges310 bronze badges

answered Feb 6, 2014 at 14:55

Andres

10.7k4 gold badges50 silver badges65 bronze badges

Collectives™ on Stack Overflow

Array initialization

2 Answers 2

1 Comment

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Related