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Unity freezes at IndexOutOfRangeException, even though I continue

I have this "Game" class that gets instantiated at Start and sets up the field for Minesweeper and in this process I count the adjacent Mines for each field.
using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Game
{
public int Width;
public int Height;
public int NumOfMines;
public Field[,] Board;
public Game(int width = 8, int height = 8, int numOfMines = 10)
{
this.Width = width;
this.Height = height;
this.NumOfMines = numOfMines;
Board = new Field[height, width];
InitializeBoard();
}
public void InitializeBoard()
{
for (int row = 0; row < Height; row++)
{
for (int column = 0; column < Width; column++)
{
Board[row, column] = new Field();
}
}
// Board.Initialize();
// foreach (var field in Board)
// {
// field.IsMine = false;
// }
var rnd = new System.Random();
for (int i = 0; i < NumOfMines; i++)
{
int mineRow = 0;
int mineColumn = 0;
do
{
mineRow = rnd.Next(Height);
mineColumn = rnd.Next(Width);
} while (Board[mineRow, mineColumn].IsMine);
Board[mineRow, mineColumn].IsMine = true;
Board[mineRow, mineColumn].NumOfAdjacentMines = null;
}
for (int row = 0; row < Height; row++)
{
for (int column = 0; column < Width; column++)
{
if (!Board[column, row].IsMine)
Board[row, column].NumOfAdjacentMines = CountAdjacentMines(new Vector2Int(column, row));
}
}
}
private int CountAdjacentMines(Vector2Int pos)
{
Debug.Log(pos);
int counter = 0;
for (int y = pos.y - 1; y <= pos.y + 1; y++)
{
for (int x = pos.x - 1; y <= pos.x + 1; x++)
{
try
{
Debug.Log($"Checking {x + ":" + y} for a mine");
if (Board[x, y].IsMine)
{
counter++;
}
}
catch (Exception ex)
{
Debug.LogError(ex + ", Pos: " + x + ":" + y);
continue;
}
}
}
return counter;
}
}
Why does Unity freeze without any notes? If I throw the exception, unity reacts normally.
(I have to write this so StackOverflow let's me post this...)

Look at the inner for loop iterating the x variable. Look closely. What is the actual condition that will end/conclude this inner for loop? Look very closely.
Basic answer to your question: Your program freezes, because the inner for loop iterating the x variable is an infinite loop that will never end. It's not Unity that freezes, it's your code getting stuck in this infinite loop. Like a hamster running in his wheel, forever...
(Re)throwing the exception will force this loop to exit, hence no freeze (because, simplified speaking, throwing the exception will abort execution of the CountAdjacentMines method).

NxN matrix with n from user input and default values if no n provided

I need to make a Jacobi Gauss program but I'm struggling with the start of it. We need to create a class which encapsulates a nxn matrix and stores it in a 2D array, with the default value being 3x3 with all values 0. We then have to add features to this and the rest of the Jacobi Gauss model. I've tried a few ways to make a matrix but I can't get one that relies on user input for size or defaults to a set size/values.

There are many ways to represent 2d matrix but the most simple is just as a native 2d array. By default a new array is filled with default values which for ints is zero. You can initialize yourself. Or, of course you can simply set the values after you create it.
Note in the first case I've created the array based off a integer. In this case for simplicity 1 value, obviously it does not have to be square.
static void Main(string[] _)
{
int dimensions = 3;
int[,] matrix = new int[dimensions, dimensions];
foreach (var v in matrix)
Console.WriteLine(v);
int[,] matrix2 = new int[,] { { 1,1,1},{ 2,2,2},{ 3,3,3} };
for (int x = 0; x < dimensions; ++x)
{
for (int y = 0; y < dimensions; ++y)
{
// matrix2[x,y] = whatever...
Console.WriteLine(matrix2[x, y]);
}
}
}
One option to wrap this in a class is to use a indexer method. For a simple square matrix with absolutely no error handling that might look like this:
public class MyMatrix
{
int[,] data = null;
public MyMatrix(int dims = 3)
{
this.data = new int[dims, dims];
}
public void SetDimensions(int dims)
{
if (this.data.GetLowerBound(0) != dims)
{
this.data = new int[dims, dims];
for (int x = 0; x < dims; ++x)
for (int y = 0; y < dims; ++y)
this.data[x, y] = 0;
}
}
public int this[int x, int y]
{
get { return this.data[x, y]; }
set { this.data[x, y] = value; }
}
public int Size => this.data.GetLowerBound(0);
}
static void Main(string[] _)
{
MyMatrix m = new MyMatrix(3);
for (int x = 0; x < m.Size; ++x)
{
for (int y = 0; y < m.Size; ++y)
{
// m[x,y] = whatever...
Console.WriteLine(m[x, y]);
}
}
}

Bubble sort is not working

Currently the user is able to input numbers into the ListBox, and I want the ListBox to be sorted by the bubble sort below when a sort checkbutton is clicked. However, it only outputs the index number e.g. 0,1,2,3... I am not allowed to use any array or containers just the items property and parsing and converting.
private void sorted()
{
int a = Convert.ToInt32(lstHoldValue.Items.Count);
int temp;
for (int i = 0; i < a; i++)
{
for (int j = i + 1; j < a; j++)
{
if (Convert.ToInt32(lstHoldValue.Items[i]) >
Convert.ToInt32(lstHoldValue.Items[j]))
{
temp = Convert.ToInt32(lstHoldValue.Items[i]);
(lstHoldValue.Items[i]) = Convert.ToInt32(lstHoldValue.Items[j]);
(lstHoldValue.Items[j]) = temp;
}
}
}
lstHoldValue.Items.Clear();
for (int i = 0; i < a; i++)
{
Convert.ToInt32(lstHoldValue.Items.Add("\t" + i));
}
}

This is more like a Bubble sort algorithm:
private void BubbleSort()
{
int a = lstHoldValue.Items.Count;
for (int i = 0; i < a - 1; i++)
{
var k = 0;
for(var j = 1; j < a - i; j++)
{
if (Convert.ToInt32(lstHoldValue.Items[j]) < Convert.ToInt32(lstHoldValue.Items[k]))
{
var temp = lstHoldValue.Items[j];
lstHoldValue.Items[j] = lstHoldValue.Items[k];
lstHoldValue.Items[k] = temp;
k = j;
}
else
{
k++;
}
}
}
}
It will sort the numbers in the Items collection of your lstHoldValue listBox control

If the item in the ListBox is not an integer, then it is sorted as zero (0).
This sets bubbleUp to true indicating that a swap has been made in the list box. This variable is used to indicate that a swap has/has not been made in the last comparison. Entering the while(bubbleUp) sets bubbleUp to false to indicate that no swaps have been made. Then a loop through each item in the list box to compare adjacent items and swap if needed. If a swap is made, bubbleUp gets set to true indicating that the sort is not finished. bubbleUp only needs to be set once in the for loop to indicate another iteration is necessary. CheckItem is the conversion from string to integer. Hope this helps.
private void sorted()
{
bool bubbleUp = true;
string temp = "";
while (bubbleUp)
{
// bubble up adjacent values
bubbleUp = false;
for (int i = 0; i < _ListBox.Items.Count - 1; i++)
{
if (CheckItem(_ListBox.Items[i].ToString()) > CheckItem(_ListBox.Items[i + 1].ToString()))
{
temp = _ListBox.Items[i].ToString();
_ListBox.Items[i] = _ListBox.Items[i + 1];
_ListBox.Items[i + 1] = temp;
bubbleUp = true;
}
}
}
}
private int CheckItem(string inItem)
{
int value;
if (int.TryParse(inItem, out value))
return value;
return 0;
}
private void button1_Click(object sender, EventArgs e)
{
sorted();
}

How to Save a Multidimensional Array Index?

Basically my first task was to save the position of the '0' in an integer. Real simple with a standard array. This code loops through an array (Size: 8) until it locates the 0, then save that as the position. See code below:
p.s: n is a reference to an array saved somewhere else.
int position = 0;
this.nodesExpanded++;
// Loop through the array to get the position of where '0' is
for (int i = 0; i < n.getPuzzle().length; i++){
if (n.getPuzzle()[i] == 0){
position = i;
break;
}
}
My ultimate task was to make this possible for a multidimensional array (Size: [3, 3]). So here's what I've created thus far:
for (int x = 0; x < 3; x++)
{
for (int y = 0; y < 3; y++)
{
if (n.getPuzzle()[x,y] == 0)
{
**position = ;**
break;
}
}//end y loop
}//end x loop
So how do I go about saving an array reference to a location to a value?
'position' will need to be something other than int I'm guessing..
If you need more clarification be sure to comment, sorry in advance & thank you!

You can use a Tuple to store that position. Or you can create your own data structure.
Example: at the end you can see how to access tuple items.
var positions = new List<Tuple<int, int>>();
for (int x = 0; x < 3; x++)
{
for (int y = 0; y < 3; y++)
{
if (n.getPuzzle()[x,y] == 0)
{
positions.Add(new Tuple<int, int>(x,y));
break;
}
}//end y loop
}//end x loop
if(positions.Any())
{
var xpos = positions[0].Item1;
var ypos = positions[0].Item2;
}

I find a natural way to store a multidimensional array index is to use a single dimensional array whose size is the number of dimensions.
So if you have a object[,,] A and index int[] i you would index into A with the expression A[i[0],i[1],i[2]].

It works the same way as your one-dimensional array, but you have two position values to keep. I've used ints for the example, but you may want to use a custom structure or Tuple (as AD.Net) said.
int xpos = -1;
int ypos = -1;
for (int x = 0; x < 3; x++)
{
for (int y = 0; y < 3; y++)
{
if (n.getPuzzle()[x,y] == 0)
{
xpos = x;
ypos = y;
break;
}
}//end y loop
}//end x loop
if (!(xpos > -1 && ypos > -1)) ; // 0 was not found

Rotating matrices

Objectives
Imagine that, we have matrix like
a11 a12 a13
a21 a22 a23
a31 a32 a33
What I want to do is, from textbox value rotate this matrix so that, for example if I write 2 and press rotate, program must keep both diagonal values of matrix (in this case a11, a22, a33, a13, a31) and rotate 2 times clockwise other values. So result must be like
a11 a32 a13
a23 a22 a21
a31 a12 a33
It must work for all N x N size matrices, and as you see every 4 rotation takes matrix into default state.
What I've done
So idea is like that, I have 2 forms. First takes size of matrix (1 value, for example if it's 5, it generates 5x5 matrix). When I press OK it generates second forms textbox matrix like that
Form 1 code
private void button1_Click(object sender, EventArgs e)
{
int matrixSize;
matrixSize = int.Parse(textBox1.Text);
Form2 form2 = new Form2(matrixSize);
form2.Width = matrixSize * 50 + 100;
form2.Height = matrixSize *60 + 200;
form2.Show();
//this.Hide();
}
Form 2 code generates textbox matrix from given value and puts random values into this fields
public Form2(int matrSize)
{
int counter = 0;
InitializeComponent();
TextBox[] MatrixNodes = new TextBox[matrSize*matrSize];
Random r = new Random();
for (int i = 1; i <= matrSize; i++)
{
for (int j = 1; j <= matrSize; j++)
{
var tb = new TextBox();
int num = r.Next(1, 1000);
MatrixNodes[counter] = tb;
tb.Name = string.Format("Node_{0}{1}", i, j);
Debug.Write(string.Format("Node_{0}{1}", i, j));
tb.Text = num.ToString();
tb.Location = new Point(j * 50, i * 50);
tb.Width = 30;
tb.Visible = true;
this.splitContainer1.Panel2.Controls.Add(tb);
counter++;
}
}
}
Form 2 has 1 textbox for controlling rotation (others are generated on the fly, programmatically). What I want to do is, when I enter rotation count and press Enter on this textbox, I want to rotate textbox matrix as I explained above. Can't figure out how to do it.

Copy both diagonals to separate arrays, then rotate your matrix and replace diagonals. Below code shows each step:
class Program
{
static void Main(string[] args)
{
int matrixSize = 3;
string[,] matrix = new string[matrixSize,matrixSize];
//create square matrix
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
matrix[x, y] = "a" + (x + 1).ToString() + (y + 1).ToString();
}
}
Console.WriteLine(Environment.NewLine + "Base square matrix");
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
Console.Write(matrix[x, y] + " ");
}
Console.Write(Environment.NewLine);
}
Console.ReadKey();
//copy diagonals
string[] leftDiagonal = new string[matrixSize];
string[] rightDiagonal = new string[matrixSize];
for (int x = 0; x < matrixSize; x++)
{
leftDiagonal[x] = matrix[x, x];
rightDiagonal[x] = matrix[matrixSize - 1 - x, x];
}
Console.WriteLine(Environment.NewLine + "Diagonals");
for (int x = 0; x < matrixSize; ++x)
{
Console.Write(leftDiagonal[x] + " " + rightDiagonal[x] + Environment.NewLine);
}
Console.ReadKey();
//rotate matrix
string[,] rotatedMatrix = new string[matrixSize, matrixSize];
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
rotatedMatrix[x, y] = matrix[matrixSize - y - 1, x];
}
}
Console.WriteLine(Environment.NewLine + "Rotated");
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
Console.Write(rotatedMatrix[x, y] + " ");
}
Console.Write(Environment.NewLine);
}
Console.ReadKey();
//rotate matrix again
string[,] rotatedMatrixAgain = new string[matrixSize, matrixSize];
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
rotatedMatrixAgain[x, y] = rotatedMatrix[matrixSize - y - 1, x];
}
}
Console.WriteLine(Environment.NewLine + "Rotated again");
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
Console.Write(rotatedMatrixAgain[x, y] + " ");
}
Console.Write(Environment.NewLine);
}
Console.ReadKey();
//replace diagonals
for (int x = 0; x < matrixSize; x++)
{
rotatedMatrixAgain[x, x] = leftDiagonal[x];
rotatedMatrixAgain[matrixSize - 1 - x, x] = rightDiagonal[x];
}
Console.WriteLine(Environment.NewLine + "Completed" + Environment.NewLine);
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
Console.Write(rotatedMatrixAgain[x, y] + " ");
}
Console.Write(Environment.NewLine);
}
Console.ReadKey();
}
}

I don't know C#, so I can only give a suggestion in pseudocode:
Input: An N by N matrix in
Output: The input matrix rotated as described in the OP out
for i = 1 to N
for j = 1 to N
if N - j != i and i != j // Do not change values on either diagonal
out[j][N-i] = in[i][j]
else
out[i][j] = in[i][j]
Disclaimer: This algorithm is untested. I suggest you use a debugger to check that it works as you want.

This seems like quite an unorthodox UI presentation, but you're not too far off in terms of being able to achieve your functionality. Instead of a linear array, a rectangular array will make your job much easier. The actual rotation could be implemented with a for loop repeating a single rotation (which would be implemented as in the case 1 code), but I've decided to combine them into the four possible cases. This actually allows you to enter a negative number for number of rotations. Which reminds me, you really should do more error checking. At least protect against int.Parse throwing an exception both places it's used (with a try catch block or by switching to int.TryParse) and make sure it returns a meaningful number (greater than 0, possibly set a reasonable maximum other than int.MaxValue) for matrixSize in button1_Click.
namespace RotatingMatrices
{
public class Form2 : Form
{
// note these class fields
private TextBox[,] matrixNodes;
private int matrixSize;
public Form2(int matrSize)
{
InitializeComponent();
// note these inits
matrixSize = matrSize;
matrixNodes = new TextBox[matrixSize, matrixSize];
Random r = new Random();
// note the new loop limits
for (int i = 0; i < matrixSize; i++)
{
for (int j = 0; j < matrixSize; j++)
{
var tb = new TextBox();
int num = r.Next(1, 1000);
// note the change in indexing
matrixNodes[i,j] = tb;
tb.Name = string.Format("Node_{0}_{1}", i, j);
Debug.Write(string.Format("Node_{0}_{1}", i, j));
tb.Text = num.ToString();
tb.Location = new Point(j * 50, i * 50);
tb.Width = 30;
tb.Visible = true;
this.splitContainer1.Panel2.Controls.Add(tb);
}
}
}
private void buttonRotate_Click(object sender, EventArgs e)
{
string[,] matrix = new string[matrixSize, matrixSize];
int rotations = (4 + int.Parse(textBoxRotations.Text)) % 4; // note the addition of and mod by 4
switch(rotations)
{
case 1: // rotate clockwise
for (int i = 0; i < matrixSize; i++)
{
for (int j = 0; j < matrixSize; j++)
{
matrix[j, matrixSize - i - 1] = matrixNodes[i, j].Text;
}
}
break;
case 2: // rotate 180 degrees
for (int i = 0; i < matrixSize; i++)
{
for (int j = 0; j < matrixSize; j++)
{
matrix[i, j] = matrixNodes[matrixSize - i - 1, matrixSize - j - 1].Text;
}
}
break;
case 3: // rotate counter-clockwise
for (int i = 0; i < matrixSize; i++)
{
for (int j = 0; j < matrixSize; j++)
{
matrix[i, j] = matrixNodes[j, matrixSize - i - 1].Text;
}
}
break;
default: // do nothing
return;
}
// restore diagonals
for(int i = 0; i < matrixSize; i++)
{
matrix[i, i] = matrixNodes[i, i].Text;
matrix[i, matrixSize - i - 1] = matrixNodes[i, matrixSize - i - 1].Text;
}
// write strings back to text boxes
for (int i = 0; i < matrixSize; i++)
{
for (int j = 0; j < matrixSize; j++)
{
matrixNodes[i, j].Text = matrix[i, j];
}
}
}
}
}

I decided to tackle the issue using a listView instead of a text box, which makes the logic easier for me. Using this method, I was able to think of the matrix as successive boxes. I start on the outside and move in toward the middle, changing the size of my box each time.
Also, rather than using two forms, I use one. At the top I have a textbox where the user enters the size they want the array to be, and a button labeled "Fill" (button2). And at the bottom I have a textbox where the user enters the degree of rotation. When they click "Rotate," it kicks off a process of adding values to linked lists, combining and shifting the list, and then writing back out to the matrix. I'm sure I made it more convoluted than it has to be, but it was a great learning exercise.
After looking over jerry's code above, I think I'm going to look into rectangular arrays. :)
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace Recycle
{
public partial class Form1 : Form
{
public int size;
public LinkedList<string> topRight = new LinkedList<string>();
public LinkedList<string> bottomLeft = new LinkedList<string>();
public LinkedList<string> myMatrix = new LinkedList<string>();
public LinkedList<string> shiftMatrix = new LinkedList<string>();
public Form1()
{
InitializeComponent();
}
private void button2_Click(object sender, EventArgs e)
{
listView1.Clear();
size = int.Parse(textBox2.Text);
int c = 0;
int q = 0;
int w = 0;
string[] content = new string[size];
Random rnd = new Random();
for (c = 0; c < size; c++)
{
listView1.Columns.Add("", 25);
}
for (q = 0; q < size; q++)
{
for (w = 0; w < size; w++)
{
content[w] = rnd.Next(9,100).ToString();
}
ListViewItem lvi = new ListViewItem(content);
listView1.Items.Add(lvi);
}
}
public bool iseven(int size)
{
if (size % 2 == 0)
{
return true;
}
else
{
return false;
}
}
public void button1_Click(object sender, EventArgs e)
{
if (listView1.Items.Count < 3)
{
MessageBox.Show("Matrix cannot be rotated.");
return;
}
bool even = false;
int shift = int.Parse(textBox1.Text); //amount to shift by
int box = listView1.Items.Count - 1; //size of box
int half = Convert.ToInt32(listView1.Items.Count / 2);
int corner = 0; //inside corner of box
if (shift > listView1.Items.Count)
{
shift = shift % ((listView1.Items.Count - 2) * 4);
}
do
{
eachPass(shift, box, corner);
++corner;
--box;
} while (box >= half + 1);
}
public void eachPass(int shift, int box, int corner)
{
int x;
int i;
//Read each non-diagonal value into one of two lists
for (x = corner + 1; x < box; x++)
{
topRight.AddLast(listView1.Items[corner].SubItems[x].Text);
}
x = box;
for (i = corner + 1; i < box; i++)
{
topRight.AddLast(listView1.Items[i].SubItems[x].Text);
}
for (x = box - 1; x > corner; x--)
{
bottomLeft.AddLast(listView1.Items[box].SubItems[x].Text);
}
x = corner;
for (i = box - 1; i > corner; i--)
{
bottomLeft.AddLast(listView1.Items[i].SubItems[x].Text);
}
string myTest = "";
//join the two lists, so they can be shifted
foreach (string tR in topRight)
{
myMatrix.AddLast(tR);
}
foreach (string bL in bottomLeft)
{
myMatrix.AddLast(bL);
}
int sh;
//shift the list using another list
for (sh = shift; sh < myMatrix.Count; sh++)
{
shiftMatrix.AddLast(myMatrix.ElementAt(sh));
}
for (sh = 0; sh < shift; sh++)
{
shiftMatrix.AddLast(myMatrix.ElementAt(sh));
}
//we need the sizes of the current lists
int trCnt = topRight.Count;
int blCnt = bottomLeft.Count;
//clear them for reuse
topRight.Clear();
bottomLeft.Clear();
int s;
//put the shifted values back
for (s = 0; s < trCnt; s++)
{
topRight.AddLast(shiftMatrix.ElementAt(s));
}
for (s = blCnt; s < shiftMatrix.Count; s++)
{
bottomLeft.AddLast(shiftMatrix.ElementAt(s));
}
int tRn = 0;
int bLn = 0;
//write each non-diagonal value from one of two lists
for (x = corner + 1; x < box; x++)
{
listView1.Items[corner].SubItems[x].Text = topRight.ElementAt(tRn);
++tRn;
}
x = box;
for (i = corner + 1; i < box; i++)
{
listView1.Items[i].SubItems[x].Text = topRight.ElementAt(tRn);
++tRn;
}
for (x = box - 1; x > corner; x--)
{
listView1.Items[box].SubItems[x].Text = bottomLeft.ElementAt(bLn);
++bLn;
}
x = corner;
for (i = box - 1; i > corner; i--)
{
listView1.Items[i].SubItems[x].Text = bottomLeft.ElementAt(bLn);
++bLn;
}
myMatrix.Clear();
shiftMatrix.Clear();
topRight.Clear();
bottomLeft.Clear();
}
}
}