Inserting new values into Array after inital popluation

[rholmes464]

I have been reading these forums and have not found the answer so please excuse if my first post is a little ...not organized?
I have an Multidimension Array that I am trying to populate via user input (have to use array) and that I can do, for the first 2 numbers. My issue is subsequent numbers (in the same session) - they always replace the first two entries. My thought process was that I would check to see if there was already data in the array and then insert the new data after the current info. But Alas, I have not been able to figure it out. Not asking to solve, but pointing me in the right direction would be greatly appreciated. (will try to post code below)
<code>
public void rh_add_arrays(double num8,double num9){
for(counter=0; counter<1;++counter)
{
for(counter2=0;counter2<=counter;counter2++)
{
if(counter > rh1.length)
{
** have not put the error message here yet**
}
else{
rh1[counter][0]= num8;
rh1[counter][1]= num9;
System.out.println("made it here");
}
}
}
</code>
I tried to check the rh1.index value and havent been able to make it fail (i.e. if rh1.length is not filled do this)
Thank you for your time

[doWhile]

Consider using a List (for example an ArrayList (Java Platform SE 6) ), which will allow you to readily append values to the object...further, rather than having a 2 index arrays, create a class which holds these values should the values be associated with each other.

[rholmes464]

Thanks for the quick response, I actually started out with an ArrayList (which was very easy to do) but the instructor is requiring an array. It's been about 7 years since doing java and well I am extremely rusty.

[Norm]

they always replace the first two entries

rh1[counter][0]= num8;
rh1[counter][1]= num9;

That's exactly what the two lines of code do: replace the first two entries.
Instead of hardcoding indexes of 0 and 1, use variables to put the numbers somewhere else in the array.

[rholmes464]

I changed from
rh1[counter][0] = num8;
rh1[counter][1] = num9;

to
<code>
rh1[counter][counter2]= num8;
rh1[counter2][counter2]= num9;
</code>
and so far through testing it is working

thanks to all for the advice :)

[rholmes464]

Upon changing the code to this
<code>
for(counter=0; counter<2;++counter)
{

for(counter2=0;counter2<rh1[counter].length;++counter2)
{
rh1[counter][a] = num8;
rh1[counter2][j]= num9;
}
++counter;
a++;
j++;
}
It increments but i dont know if it is doing it correctly - while debugging the code I notice that it is populating the array thusly
1st run : input : 1, 2 -> rh1(0) : [0][1] : 1.0 / 0.0 rh1(1): [1][0]: 2.0 /0.0
2nd run: 11,22 -> rh1(0): [0][1]: 1.0/11.0 rh1(1): [1][0]: 2.0 /22.0
so excuse the stupid question - but is that correct?

[Norm]

is that correct?

You're the one that has to answer that. Does the code do what you want it to do?

You are incrementing the variable: counter two times. Is that what you want?

Normally the incrementing is by post operator: count++


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[rholmes464]

I apologize if I misspoke - It is incrementing like I want, my question arose from me thinking that it would increment [0][1] - 1st set then [1][1] next set, and so on and so forth - it's most likely my not understanding of how the arrays increment - more research to do
thanks!