still learning

[rscorpio64]

here is a snipped:

int[][] c = new int [9][2];
 
...
 
c[4][2] = -1;
 
 
 
 

Why does that not work?

[sukatoa]

will you post the experimental code that makes you convinced it is not working?

[rscorpio64]

sorry all my arrays give me an out of bounds error

so if i have a array_example[2][9]
and i assign array_example[2][9] = 15

it gives me an out of bouds error

if i change the declaraation to array_example[3][10]

then it works!!

why?
There really is no program because no matter what program i use arrays in, I get this type of error. (btw I know pascal, vb (all basics) delphi, javascript and a few others so its easy for me to get the methods mixed up)

help

[JosAH]

why?
help

If you declare an array to have 'n' elements the valid index values are:

0, 1, 2, 3 ... n-3, n-2, n-1 (count them all for reasonable values of 'n').

That's why; Java always starts its indexing at element number zero,

kind regards,

Jos

[rscorpio64]

If you declare an array to have 'n' elements the valid index values are:

0, 1, 2, 3 ... n-3, n-2, n-1 (count them all for reasonable values of 'n').

That's why; Java always starts its indexing at element number zero,

kind regards,

Jos

correct - as a mater of fact the majority of programing languages start with zero on arrays

what throws me off is for example:
pascal theArray[1..10,1..5] wil give me a 10 x 5 array
basic theArray(10,5) same - 10 x 5 array

is what your saying is that the following:
theArray[10][5]
will NOT give me a 10x5 array (excluding the fact that it really is since your starting at zero) to the extent that I cannot reach the max theArray[10][5]= n ?

bear in mind that the above two examples (pascal and basic) you can STILL use [0,0] (pascal) and (0,0)(basic) to use as data.

in conclusion - so I understand java arrays - in order to achieve a 10 x 5 array (in this example) and reach those numbers (i.e. theArray[10][5] = n) it actually needs to read theArray[11][6]?

(or I suppose I could n-- for the count.

as an after thought, kinda defeats the purpose of making a chessboard[8][8] and only have access to 0 - 7 even though your looking at the number "8" in the dimension. lol

[JosAH]

as an after thought, kinda defeats the purpose of making a chessboard[8][8] and only have access to 0 - 7 even though your looking at the number "8" in the dimension. lol

You can't count; a board[8][8] gives you an 8x8 board indexed by the values
0,1,2,3,4,5,6 and 7 (those are eight index values).

kind regards,

Jos