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Filling 2D Array in Java and getting ExceptionOutOfBounds

I searched some entries, but could not answer my question correctly myself.
I'm trying to fill a 2-dimensional array with values.
As a test I'm currently doing this by trying to fill the array with the int number 1.
I do not understand my mistake.
public static void creatBoard () {
final int L = 6;
final int H = 6;
// Modell:
int [] [] board = new int [L] [H];
for (int i = 0; i<=board.length; i++) {
for (int j = 0; j<=board.length; j++) {
board [i] [j] = 1;
}
System.out.println("");
}

Use index 0 to length-1 (as array index start with 0)
public static void creatBoard () {
final int L = 6;
final int H = 6;
// Modell:
int [] [] board = new int [L] [H];
for (int i = 0; i<board.length; i++) {
for (int j = 0; j<board[i].length; j++) {
board [i] [j] = 1;
}
System.out.println("");
}
}

just debug it and you can see, that
for (int i = 0; i<=board.length; i++) {
for (int j = 0; j<=board.length; j++) {
board [i] [j] = 1;
}
System.out.println("");
}
i, and j change values from 0 to 6, it means that it get's out of arrays bounds ( you iterate over 7 lements, instead of 6 ), just remove = sign in loop bodies
for (int i = 0; i<board.length; i++) {
for (int j = 0; j<board[i].length; j++) {
board [i] [j] = 1;
}
System.out.println("");
}

Your board array is of size 6x6 hence the board.length is 6.
When you run the loop for (int j = 0; j<=board.length; ij+) it will run from 0 up to 6 but the array indexing is from 0 to 5. So when j=6, ExceptionOutOfBounds occurs since it will be referring to index board[0][6].
Change the condition in both the loops from <=board.length to <board.length

printing numbers with nested loops

I have to print the following numbers using nested loops, and I kinda have an idea how, but not how to execute it.
000111222333444555666777888999
000111222333444555666777888999
000111222333444555666777888999
My code so far is something like:
public class opgave_2 {
public static void main(String[] args) {
final int first = 3;
final int second = 3;
final int third = 9;
for (int i = 0; i <= first ; i++) {
for (int j = i; j <= second; j++) {
for (int k = j; k <= third; k++) {
System.out.print(i);
}
}
}
}
}

You should proceed by steps to resolve such problem.
First, you want to print a number 3 times :
int myNumber = 0;
for(int i=0; i<3; i++) {
System.out.print(myNumber);
}
Second, you want to repeat it 9 times and your number to vary from 0 to 9 (seems like an index of loop) :
for(int myNumber=0; myNumber<=9; myNumber++) {
for(int i=0; i<3; i++) {
System.out.print(myNumber);
}
}
Third, you want to display this line 3 times :
for(intj=0; j<3; j++) {
for(int myNumber=0; myNumber<=9; myNumber++) {
for(int i=0; i<3; i++) {
System.out.print(myNumber);
}
}
System.out.println(""); //new line
}

What about something like this:
for (int i = 0; i < 3; i++) {
for (int j = 0; j <= 9; j++) {
System.out.printf("%1$s%1$s%1$s", j);
}
System.out.println();
}
Which uses 2 nested loops. The first to print the line 3 times, and the second to print the numbers per line

you can use a loop, that loops 3 times. in that you put a loop that prints every number from 0 to 9 3 times in a row within the same line
for(int a = 0; a < 3; a++){
for(int i = 0; i < 10; i++){
System.out.print(i+""+i+""+i);
}
System.out.println(); //for the new line
}
or
for(int a = 0; a < 3; a++){
for(int i = 0; i < 10; i++){
System.out.print(i);
System.out.print(i);
System.out.print(i);
}
System.out.println(); //for the new line
}
this should do

How to create two dimensional grid with two-d. array?

This is my current code:
public static void main(String[] args) {
int [][] twoD = new int [5][5];
/*for(int i = 0; i<5; i++){
for(int j = 0; j<5; j++){
System.out.print(twoD[i][j] + "");
}
}*/
}
}
I can't seem to do it. I got confused and I removed the part of testing w/commenting. Just ignore that.
I am aiming to get a two dimensional array like this:
1 2 3 4 5
2 4 6 8 10
3 6 9 12 15
4 8 12 16 20
5 10 15 20 25
However, I just don't get it. How can I get that result? I'm a beginner at java.

First, you need to populate the array with data, and you forgot System.out.println for each row of the array.
int [][] twoD = new int [5][5];
// populate array with data
for(int i = 0; i<5; i++){
for(int j = 0; j<5; j++){
twoD[i][j] = (j+1)*(i+1);
}
}
// print result
for(int i = 0; i<5; i++){
for(int j = 0; j<5; j++){
System.out.print(twoD[i][j]);
System.out.print(" ");
}
System.out.println();
}

You have to populate the data as well:
int[][] arr = new int [5][5];
for(int i = 0; i<5; i++){
for(int j = 0; j<5; j++){
arr[i][j] = (j+1)*(i+1);
}
}
And the code to print would be:
for(int i = 0; i<5; i++){
for(int j = 0; j<5; j++){
System.out.print(arr[i][j] + " ");
}
System.out.println();
}

You are doing fine, you just need to put line jump System.out.println(); every time the second for ends
for(int i = 0; i<5; i++){
for(int j = 0; j<5; j++){
System.out.print(twoD[i][j] + " ");
}
System.out.println();
}

You are on the right track, that for loop will print out the array like that, all you need to do is print a new line character after finishing the for(j) loop. But, at least in the snippet you posted, you aren't actually doing any assignments, so there aren't any values in your array to print, Java will initialize all ints to zero for you.

The array doesn't just automatically populate with incrementing integers, rather each cell of the array will automatically initialized to 0, you have to set the values you want the array to contain. You can use the concept of your testing class to do this if you wish, just set each cell of the 2D array to a certain value. After that, you can print out the array, making sure to print a each row of the array on a new line. For instance:
public static void main(String[] args) {
int [][] twoD = new int [5][5];
int increment = 1;
for(int i = 0; i<5; i++){
for(int j = 0; j<5; j++){
twoD[i][j] = increment++;
}
}
for(i = 0; i<5; i++){
for(j = 0; j<5; j++){
System.out.print(twoD[i][j] + " ");
}
System.out.println();
}
}
The first set of nested for loops will set each of the cells of the 2D array to the incremented integers you want (note increment++ will first set the cell to the value increment currently is, then add one to the variable). The second set of nested for loops will print out the array as you desire.

refer this code
int[][] twoD = new int[5][5];
// add values to array
for (int i = 0; i < 5; i++) {
int val = 1;
val = val + i;
for (int j = 0; j < 5; j++) {
twoD[i][j] = val * (j + 1);;
}
}
// Print array
for (int i = 0; i < 5; i++) {
for (int j = 0; j < 5; j++) {
System.out.print(twoD[i][j] + " ");
}
System.out.println();
}

as others pointed out you need to print it nicely to see the pattern, i and j are indices of your array. However, I see that you have a nice pattern so just running two loops won't solve the problem.
Maybe something like this would help (not giving exact answer intentionally)
int [][] twoD = new int [5][5];
int i;
// initialize
int c = 1; int j = 0;
for(c=1; c<5; c++) {
for( i = 1; i<=5; i++){
twoD[i-1][c-1] = c*c*i; twoD[c-1][i-1]=c*c*i;
}
}
for( i = 0; i<5; i++) {
for( j = 0; j<5; j++) {
System.out.print(twoD[i][j]);System.out.print(" " );
}
System.out.println("\n");
}

How to jump over a specific number in a loop

Didn't know how to call my Thread.
public NaturalNumberTuple(int[] numbers) {
int [] thisTuple = new int[numbers.length];
int count = 0;
for(int j = 0; j < numbers.length; j++){
if(numbers[j] > 0){
thisTuple[j] = numbers[j];
count++;
}
}
int[] newTuple = new int[count];
for(int i = 0; i < newTuple.length; i++){
int k = i;
while(thisTuple[k] <= 0){
k++;
}
newTuple[i] = thisTuple[k];
}
this.tuple = newTuple;
}
This is my code snippet to create a new NaturalNumberTuple.
So this is the Array I want to use: int[] tT2 = {1,2,4,-4,5,4,4};
I only want to use natural numbers greater than 0 and my problem isn't to cut out the negative number but it is that my console is giving me this: Tuple(Numbers:1,2,4,5,5,4).
The problem is if I jump over that value which is negative with my while loop to get the higher (k) I will have to pass the same (k) in my for loop which I don't want to because I already got it in my Array. I hope you understand my problem.
Sorry for the bad english..
Edit: Can't use any methods from java itself like System.arrayCopy

You have an error in the first loop. Fixing it makes the second loop much simpler :
public NaturalNumberTuple(int[] numbers) {
int [] thisTuple = new int[numbers.length];
int count = 0;
for(int j = 0; j < numbers.length; j++){
if(numbers[j] > 0){
thisTuple[count] = numbers[j]; // changed thisTuple[j] to thisTuple[count]
count++;
}
}
int[] newTuple = new int[count];
for(int i = 0; i < newTuple.length; i++) {
newTuple[i] = thisTuple[i];
}
this.tuple = newTuple;
}
Of course, the second loop can be replaced with a call to System.arrayCopy.

I would change your while loop to an if that simply restarts the for loop. Say from this:
while(thisTuple[k] <= 0){
k++;
}
To something like this:
if (thisTuple[k] <= 0)
continue;
This stops you from adding the same number twice when you encounter a negative or zero number.

This code will solve you issue. The code is checked in the following link Tuple Exampple
int [] thisTuple = new int[numbers.length];
int count = 0;
for(int j = 0; j < numbers.length; j++){
if(numbers[j] > 0){
thisTuple[count] = numbers[j]; //Change to thisTuple[count]
count++;
}
}
int[] newTuple = new int[count];
for(int i = 0; i < count; i++){
newTuple[i] = thisTuple[i];
}

Arrays in for loops

I have an array called blockHeights, which contains 3 values inside of it, namely 1,2,3. So blockHeights[0] is equal to 1.
I also have a loop:
for (int i = 1; i <= blockHeights.length; i++)
In the first time around the loop, I want to create a variable called totalBlockHeights where it is
int totalBlockHeights = blockHeights[0] + blockHeights [1] + blockHeights [2];
However, in the next loop I want that variable to change, so that it only adds blockHeights[1] and blockHeights[2] together, ignoring blockHeights[0].
How would I go about doing this?

Try the following (I'm assuming the third iteration should only include blockHeights[2], following the pattern):
for (int i = 1; i <= blockHeights.length; i++) {
int totalBlockHeights;
for (int j = i - 1; j < blockHeights.length; j++) { // all block heights from here onwards
totalBlockHeights += blockHeights[j];
}
// do whatever
}

Well, if you want the sum of your array, and the sum of the array without first value
int totalBlockHeights = 0;
for(int i = 0; i < blockHeights.length; i++){
totalBlockHeights += blockHeights[i];
}
System.out.println(totalBlockHeights);
System.out.println("totalBlockHeights without first value = " + (totalBlockHeights - blockHeights[0]));
this way you only loop once

Try following code:
public class Loop {
public static void main(String[] argv) {
int[] blockHeights = new int[] {1, 2, 3};
int totalBlockHeights = 0;
for(int i = 0; i < blockHeights.length; i++) {
totalBlockHeights = 0;
for(int j = i; j < blockHeights.length; j++) {
totalBlockHeights += blockHeights[j];
}
System.out.println(totalBlockHeights);
}
}
}

int[] blockHeights = new int[] { 1, 2, 3 };
int totalBlockHeights = 0;
int customBlockHeights = 0;
for (int i = 0; i < blockHeights.length; i++) {
totalBlockHeights += blockHeights[i];
if (i == 0) {
continue;
}
customBlockHeights += blockHeights[i];
}
System.out.println(totalBlockHeights);
System.out.println(customBlockHeights);
This will print:
6
5
You dont need two for to achieve that.

you can perform this on two for loop outer loop for (int i = 1; i <= blockHeights.length; i++), and in inner loop (take a variable j) you can do like int totalBlockHeights = totalBlockHeights + blockHeights[j], and for i<j, you can just continue the for loop.
as answered by btrs20