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Array trouble

David Barry
Ranch Hand

Joined: Jan 13, 2009
Posts: 84
Can I create an array that stores the values that are incremented here: "for ( x = 1 ; x >= -1 ; x-=0.1 ) System.out.println(x);". I need to do this because I need these numbers incremented here for another calculation. If I can't form an array out of them, then what can I do to get them so I can do calculations with each one. Thanks
Steve Luke

Joined: Jan 28, 2003
Posts: 4181

Sure you can. Create a double[] and in the loop body store the value of x inside the the appropriate position in the array. You will probably need another (int) counter that increments for each step in the loop.

Why store the values? Can you move the calculation that uses the value of x inside the body of the for loop?

David Barry
Ranch Hand

Joined: Jan 13, 2009
Posts: 84
ok. Thanks for the help. I'm just not sure that I follow you here. Could you give an example? Thanks
Paul Clapham

Joined: Oct 14, 2005
Posts: 19739

The easiest way would be like this:

fred rosenberger
lowercase baba

Joined: Oct 02, 2003
Posts: 11877

if you want to store the values in an array, you'd store them like any other value. you need to declare an array big enough to hold the values you want, then you just stick them in. You could do something like this:

gives this output:

C:\slop>java Tester
x is 1.0, y is 0.
x is 0.9, y is 1.
x is 0.79999995, y is 2.
x is 0.6999999, y is 3.
x is 0.5999999, y is 4.
x is 0.4999999, y is 5.
x is 0.39999992, y is 6.
x is 0.29999992, y is 7.
x is 0.19999993, y is 8.
x is 0.09999993, y is 9.
x is -7.301569E-8, y is 10.
x is -0.100000076, y is 11.
x is -0.20000008, y is 12.
x is -0.30000007, y is 13.
x is -0.40000007, y is 14.
x is -0.50000006, y is 15.
x is -0.6000001, y is 16.
x is -0.7000001, y is 17.
x is -0.80000013, y is 18.
x is -0.90000015, y is 19.

y here is your index of the array, and x is the value. This gets a little complicated if you need to remember what each position is... it's not very intuitive that array[17] would hold (approx.) -0.7

I am assuming you did not mean that you want to use the value of 0.9 as the index to your array.

There are only two hard things in computer science: cache invalidation, naming things, and off-by-one errors
I agree. Here's the link:
subject: Array trouble
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