I have this form where textboxes holds a client's education information. I've put these textboxes in array so I can individually call them and put information to them from my datatable. I achieve this using a for loop and counter for it is the amount of rows in the datatable. I was wondering if there's a way to count the amount of items in it so I can change the counter to a much larger value and avoid all these other counters:
TextBox[] arrayE = {
txtSchoolN1, txtDegree1, txtStartD1, txtEndD1,
txtSchoolN2, txtDegree2, txtStartD2, txtEndD2,
txtSchoolN3, txtDegree3, txtStartD3, txtEndD3,
txtSchoolN4, txtDegree4, txtStartD4, txtEndD4,
txtSchoolN5, txtDegree5, txtStartD5, txtEndD5,
txtSchoolN6, txtDegree6, txtStartD6, txtEndD6,
};
int[] counter = { 0, 1, 2, 3 };
for (int x = 0; x < dataTable.Rows.Count; x++)
{
arrayE[counter[0]].Text = dataTable.Rows[x][0].ToString().Trim();
arrayE[counter[1]].Text = dataTable.Rows[x][1].ToString().Trim();
arrayE[counter[2]].Text = dataTable.Rows[x][2].ToString().Trim();
arrayE[counter[3]].Text = dataTable.Rows[x][3].ToString().Trim();
counter[0] += 4;
counter[1] += 4;
counter[2] += 4;
counter[3] += 4;
}
In a nutshell, I'm trying to shorten my code
Use a second, nested loop:
int[] counter = { 0, 1, 2, 3 };
for (int x = 0; x < dataTable.Rows.Count; x++) {
for (int i = 0; i < counter.Length; i++) {
arrayE[counter[i]].Text = dataTable.Rows[x][i].ToString().Trim();
counter[i] += 4;
}
}
Or, without the counter array:
for (int x = 0; x < dataTable.Rows.Count; x++) {
for (int y = 0; y < 4; i++) {
arrayE[4 * x + y].Text = dataTable.Rows[x][y].ToString().Trim();
}
}
Here's one way.
var arrayE = new[]
{
new[] {txtSchoolN1, txtDegree1, txtStartD1, txtEndD1},
new[] {txtSchoolN2, txtDegree2, txtStartD2, txtEndD2},
new[] {txtSchoolN3, txtDegree3, txtStartD3, txtEndD3},
new[] {txtSchoolN4, txtDegree4, txtStartD4, txtEndD4},
new[] {txtSchoolN5, txtDegree5, txtStartD5, txtEndD5},
new[] {txtSchoolN6, txtDegree6, txtStartD6, txtEndD6}
};
for (var x = 0; x < dataTable.Rows.Count; x++)
{
arrayE[x][0].Text = dataTable.Rows[x][0].ToString().Trim();
arrayE[x][1].Text = dataTable.Rows[x][1].ToString().Trim();
arrayE[x][2].Text = dataTable.Rows[x][2].ToString().Trim();
arrayE[x][3].Text = dataTable.Rows[x][3].ToString().Trim();
}
Is this short enough?
int countOne = 0;
for (int x = 0; x < dataTable.Rows.Count; x++)
{
for (int y = 0; y <= 3; y++)
{
arrayE[countOne + y].Text = dataTable.Rows[x][y].ToString().Trim();
}
countOne += 4;
}
Related
I am trying to create an array of 6 arrays each containing 4 arrays, each of those 4 arrays with different shape.
Like in the form below:
[[array([[1,2,3,4,6,5],
[5,6,6,7,7,5],
[6,6,5,5,6,5],
[4,6,6,7,7,5],
[5,6,6,7,7,5],
[6,6,5,5,6,5],
[6,6,5,5,6,5],]),
array([[9,9,9],
[9,9,9],
[6,6,6],
[3,3,6],
[6,6,6]]),
array([[6],
[7],
[7],
[7],
[7]]),
array([[7,8,8,8,8]])],
[[array([[1,2,3,4,6,5],
[5,6,6,7,7,5],
[6,6,5,5,6,5],
[4,6,6,7,7,5],
[5,6,6,7,7,5],
[6,6,5,5,6,5],
[6,6,5,5,6,5],]),
array([[9,9,9],
[9,9,9],
[6,6,6],
[3,3,6],
[6,6,6]]),
array([[6],
[7],
[7],
[7],
[7]]),
array([[7,8,8,8,8]])]]
..........
I have this code but I am doing something wrong, I do not get the desired shape.
Can somebody please help me with this?
int populationSize = 6;
double[][][][] population = new double[populationSize][][][];
int value = 3;
for (int i = 0; i < populationSize; i++)
{
population[i] = new double[4][][];
for (int j = 0; j < 4; j++)
{
const int rows = 7, cols = 6;
population[i][j] = new double[rows][];
for (int k = 0; k < rows; k++)
{
population[i][j][k] = new double[cols];
for (int m = 0; m < cols; m++)
{
population[i][j][k][m] = value;
}
}
}
}
const int rows = 7, cols = 6;
population[j][j] = new double[5][];
for (int k = 0; k < rows; k++)
you are using the same indexes for population[j][j], that is probably incorrect.
You are also specifying 7 rows, but create a matrix of size 5. That is probably incorrect.
As Scopperloit points out, you probably want:
const int rows = 7, cols = 6;
population[i][j] = new double[rows][];
for (int k = 0; k < rows; k++)
Overall when debugging problems. Run the code in a debugger and inspect the values against your expectations. Index out of range exceptions are usually very easy to debug:
What is the index?
What is the length of the array?
Is the index or array length incorrect?
I managed to solve my problem.
THis function creates an array of arrays of arrays of different shapes according to another array, and fills it with random normal standard distribution values :
int[,] netshape = new int[,] { { 3, 4}, { 4, 5}, { 4, 1 }, { 1, 4} }; // The shape of the network
public double[][][][] CreateNetwork(int[,] netshape,int populationSize )
{
normal = new MathNet.Numerics.Distributions.Normal(0, 1);// Generate random normal standard distribution
int rows, cols ;
double[][][][] population = new double[populationSize][][][];
for (int i = 0; i < populationSize; i++)
{
population[i] = new double[4][][];
for (int j = 0; j < 4; j++)
{
rows = netshape[j, 0];
cols = netshape[j, 1];
population[i][j] = new double[rows][];
for (int k = 0; k < rows; k++)
{
population[i][j][k] = new double[cols];
for (int m = 0; m < cols; m++)
{
population[i][j][k][m] = normal.Sample(); ;
}
}
}
}
return population;
}
If matrix A of size (3x3), then should i use the method of finding determinants, like grabbing the rows and column of first element and removing it from the array 2D array to get the remaining elements and then moving to the next element and repeating the same steps ?
[{1,2,3},
{4,5,6},
{7,8,9}]
I finally was able to do it, here's what I did :
enter image description here
class program
{
public static void Main()
{
int[,] arr = new int[3, 3];
Console.WriteLine("Enter elements of " + (arr.GetUpperBound(0) + 1) + "x" + (arr.GetUpperBound(1) + 1) + " matrix:");
for (int i = 0; i < (arr.GetUpperBound(0) + 1); i++)
{
for (int j = 0; j < (arr.GetUpperBound(1) + 1); j++)
{
arr[i, j] = Convert.ToInt32(Console.ReadLine());
}
}
Console.WriteLine("Matrix entered: ");
for (int i = 0; i < (arr.GetUpperBound(0) + 1); i++)
{
for (int j = 0; j < (arr.GetUpperBound(1) + 1); j++)
{
Console.Write("\t" + arr[i, j]);
}
Console.WriteLine();
}
Console.WriteLine("Possible sub-matrices: ");
for (int i = 0; i < 3; i++)
{
for (int j = 0; j< 3; j++)
{
TrimArray(i,j,arr);
}
}
}
public static int[,] TrimArray(int row, int column, int[,] original)
{
int[,] resultant = new int[original.GetLength(0) - 1, original.GetLength(1) - 1];
for (int i = 0, j = 0; i < original.GetLength(0); i++)
{
if (i == row)
continue;
for (int k = 0, u = 0; k < original.GetLength(1); k++)
{
if (k == column)
continue;
resultant[j, u] = original[i, k];
u++;
}
j++;
}
Console.WriteLine();
for (int i = 0; i < 2; i++)
{
for (int j = 0; j< 2; j++)
{
Console.Write("\t"+resultant[i,j]);
}
Console.WriteLine();
}
return resultant;
}
}
I did this for you yesterday, I created a method that will return a square matrix, given a parent matrix and the length.
static void Main(string[] args)
{
int[][] parentMatrix = new int[][]
{
new int [] { 1, 2, 3 },
new int [] { 4, 5, 6 },
new int [] { 7, 8, 9 }
};
var chunks = GetSubMatrices(parentMatrix, 2);
Console.WriteLine(chunks);
}
static List<int[][]> GetSubMatrices(int[][] parentMatrix, int m)
{
int n = parentMatrix.Length > m ? parentMatrix.Length : throw new InvalidOperationException("You can't use a matrix smaller than the chunk size");
var chunks = new List<int[][]>();
int movLimit = n - m + 1;
var allCount = Math.Pow(movLimit, 2);
for (int selRow = 0; selRow < movLimit; selRow ++)
{
for (int selCol = 0; selCol < movLimit; selCol ++)
{
// this is start position of the chunk
var chunk = new int[m][];
for (int row = 0; row < m; row++)
{
chunk[row] = new int[m];
for (int col = 0; col < m; col++)
{
chunk[row][col] = parentMatrix[selRow + row][selCol + col];
}
}
chunks.Add(chunk);
}
}
return chunks;
}
If you have any problems using it, you can simply comment below.
I needed to solve a problem like and came up with this answer. Hope it adds to your library of answers. If the submatrix specified is not greater than 1, do nothing.
public static void GetSubMatrixes(int[,] arr, int size)
{
int parentMatrixRowLength = arr.GetLength(0);
int parentMatrixColLength = arr.GetLength(1);
var overall = new List<object>();
if(size > 1)
{
for (int i = 0; i < parentMatrixRowLength; i++)
{
//get the columns
for (int j = 0; j < parentMatrixColLength; j++)
{
var subMatrix = new int[size, size];
/*if the new matrix starts from second to the last value in either the row(horizontal or column)
* do not proceed, go to the row or column in the parent matrix
* */
if (j < parentMatrixColLength - (size - 1) && i < parentMatrixRowLength - (size - 1))
{
//add
for (int m = 0; m < subMatrix.GetLength(0); m++)
{
for (int n = 0; n < subMatrix.GetLength(1); n++)
{
/*check the sum of current column value and the sum of the current row value
* of the parent column length and row length if it goes out of bounds
*/
var row = i + m; var col = j + n;
//actual check here
if (row < parentMatrixRowLength && col < parentMatrixColLength)
{
subMatrix[m, n] = arr[i + m, j + n];
}
}
}
overall.Add(subMatrix);
}
}
}
//display the sub matrixes here
for (int i = 0; i < overall.Count; i++)
{
var matrix = overall[i] as int[,];
for (int y = 0; y < matrix.GetLength(0); y++)
{
for (int x = 0; x < matrix.GetLength(1); x++)
{
Console.Write(string.Format("{0} ", matrix[y, x]));
}
Console.Write(Environment.NewLine + Environment.NewLine);
}
Console.WriteLine();
}
}
}
I am making a program, where I need to calculate linear regression, but I got stuck at inversion of a matrix.
I have
double[,] location = new double[3,3];
It was then filled with numbers, but then I do not know, how to count the inverse matrix for it like in Linear algebra.
I searched for a solution on the internet, but there was some Matrix class that I dont know how to convert my double[,] to.
So, do you know some elegant way to inverse double[,] like the inversion of matrixes in Linear algebra?
Here you have a working example, just copy the entire code into a console project and run it.
I took it from this link https://jamesmccaffrey.wordpress.com/2015/03/06/inverting-a-matrix-using-c/
using System;
using System.Collections.Generic;
using System.Linq;
namespace matrixExample
{
class Program
{
static void Main(string[] args)
{
double[][] m = new double[][] { new double[] { 7, 2, 1 }, new double[] { 0, 3, -1 }, new double[] { -3, 4, 2 } };
double[][] inv = MatrixInverse(m);
//printing the inverse
for (int i = 0; i < 3; i++)
{
for (int j = 0; j < 3; j++)
Console.Write(Math.Round(inv[i][j], 1).ToString().PadLeft(5, ' ') + "|");
Console.WriteLine();
}
}
static double[][] MatrixCreate(int rows, int cols)
{
double[][] result = new double[rows][];
for (int i = 0; i < rows; ++i)
result[i] = new double[cols];
return result;
}
static double[][] MatrixIdentity(int n)
{
// return an n x n Identity matrix
double[][] result = MatrixCreate(n, n);
for (int i = 0; i < n; ++i)
result[i][i] = 1.0;
return result;
}
static double[][] MatrixProduct(double[][] matrixA, double[][] matrixB)
{
int aRows = matrixA.Length; int aCols = matrixA[0].Length;
int bRows = matrixB.Length; int bCols = matrixB[0].Length;
if (aCols != bRows)
throw new Exception("Non-conformable matrices in MatrixProduct");
double[][] result = MatrixCreate(aRows, bCols);
for (int i = 0; i < aRows; ++i) // each row of A
for (int j = 0; j < bCols; ++j) // each col of B
for (int k = 0; k < aCols; ++k) // could use k less-than bRows
result[i][j] += matrixA[i][k] * matrixB[k][j];
return result;
}
static double[][] MatrixInverse(double[][] matrix)
{
int n = matrix.Length;
double[][] result = MatrixDuplicate(matrix);
int[] perm;
int toggle;
double[][] lum = MatrixDecompose(matrix, out perm,
out toggle);
if (lum == null)
throw new Exception("Unable to compute inverse");
double[] b = new double[n];
for (int i = 0; i < n; ++i)
{
for (int j = 0; j < n; ++j)
{
if (i == perm[j])
b[j] = 1.0;
else
b[j] = 0.0;
}
double[] x = HelperSolve(lum, b);
for (int j = 0; j < n; ++j)
result[j][i] = x[j];
}
return result;
}
static double[][] MatrixDuplicate(double[][] matrix)
{
// allocates/creates a duplicate of a matrix.
double[][] result = MatrixCreate(matrix.Length, matrix[0].Length);
for (int i = 0; i < matrix.Length; ++i) // copy the values
for (int j = 0; j < matrix[i].Length; ++j)
result[i][j] = matrix[i][j];
return result;
}
static double[] HelperSolve(double[][] luMatrix, double[] b)
{
// before calling this helper, permute b using the perm array
// from MatrixDecompose that generated luMatrix
int n = luMatrix.Length;
double[] x = new double[n];
b.CopyTo(x, 0);
for (int i = 1; i < n; ++i)
{
double sum = x[i];
for (int j = 0; j < i; ++j)
sum -= luMatrix[i][j] * x[j];
x[i] = sum;
}
x[n - 1] /= luMatrix[n - 1][n - 1];
for (int i = n - 2; i >= 0; --i)
{
double sum = x[i];
for (int j = i + 1; j < n; ++j)
sum -= luMatrix[i][j] * x[j];
x[i] = sum / luMatrix[i][i];
}
return x;
}
static double[][] MatrixDecompose(double[][] matrix, out int[] perm, out int toggle)
{
// Doolittle LUP decomposition with partial pivoting.
// rerturns: result is L (with 1s on diagonal) and U;
// perm holds row permutations; toggle is +1 or -1 (even or odd)
int rows = matrix.Length;
int cols = matrix[0].Length; // assume square
if (rows != cols)
throw new Exception("Attempt to decompose a non-square m");
int n = rows; // convenience
double[][] result = MatrixDuplicate(matrix);
perm = new int[n]; // set up row permutation result
for (int i = 0; i < n; ++i) { perm[i] = i; }
toggle = 1; // toggle tracks row swaps.
// +1 -greater-than even, -1 -greater-than odd. used by MatrixDeterminant
for (int j = 0; j < n - 1; ++j) // each column
{
double colMax = Math.Abs(result[j][j]); // find largest val in col
int pRow = j;
//for (int i = j + 1; i less-than n; ++i)
//{
// if (result[i][j] greater-than colMax)
// {
// colMax = result[i][j];
// pRow = i;
// }
//}
// reader Matt V needed this:
for (int i = j + 1; i < n; ++i)
{
if (Math.Abs(result[i][j]) > colMax)
{
colMax = Math.Abs(result[i][j]);
pRow = i;
}
}
// Not sure if this approach is needed always, or not.
if (pRow != j) // if largest value not on pivot, swap rows
{
double[] rowPtr = result[pRow];
result[pRow] = result[j];
result[j] = rowPtr;
int tmp = perm[pRow]; // and swap perm info
perm[pRow] = perm[j];
perm[j] = tmp;
toggle = -toggle; // adjust the row-swap toggle
}
// --------------------------------------------------
// This part added later (not in original)
// and replaces the 'return null' below.
// if there is a 0 on the diagonal, find a good row
// from i = j+1 down that doesn't have
// a 0 in column j, and swap that good row with row j
// --------------------------------------------------
if (result[j][j] == 0.0)
{
// find a good row to swap
int goodRow = -1;
for (int row = j + 1; row < n; ++row)
{
if (result[row][j] != 0.0)
goodRow = row;
}
if (goodRow == -1)
throw new Exception("Cannot use Doolittle's method");
// swap rows so 0.0 no longer on diagonal
double[] rowPtr = result[goodRow];
result[goodRow] = result[j];
result[j] = rowPtr;
int tmp = perm[goodRow]; // and swap perm info
perm[goodRow] = perm[j];
perm[j] = tmp;
toggle = -toggle; // adjust the row-swap toggle
}
// --------------------------------------------------
// if diagonal after swap is zero . .
//if (Math.Abs(result[j][j]) less-than 1.0E-20)
// return null; // consider a throw
for (int i = j + 1; i < n; ++i)
{
result[i][j] /= result[j][j];
for (int k = j + 1; k < n; ++k)
{
result[i][k] -= result[i][j] * result[j][k];
}
}
} // main j column loop
return result;
}
}
}
I guess this is what you are looking for:
static double[][] MatrixInverse(double[][] matrix)
{
// assumes determinant is not 0
// that is, the matrix does have an inverse
int n = matrix.Length;
double[][] result = MatrixCreate(n, n); // make a copy of matrix
for (int i = 0; i < n; ++i)
for (int j = 0; j < n; ++j)
result[i][j] = matrix[i][j];
double[][] lum; // combined lower & upper
int[] perm;
int toggle;
toggle = MatrixDecompose(matrix, out lum, out perm);
double[] b = new double[n];
for (int i = 0; i < n; ++i)
{
for (int j = 0; j < n; ++j)
if (i == perm[j])
b[j] = 1.0;
else
b[j] = 0.0;
double[] x = Helper(lum, b); //
for (int j = 0; j < n; ++j)
result[j][i] = x[j];
}
return result;
}
See Test Run - Matrix Inversion Using C# for reference.
The task:
1. Make a matrix n by m and fill it with data from console.
2. Find the 3*3 sub matrix with the greatest sum.
{
static int[,] ArrayReadConsole()
{
Console.WriteLine("please enter n:");
int n;
n = Int32.Parse(Console.ReadLine());
Console.WriteLine("please enter m:");
int m;
m = Int32.Parse(Console.ReadLine());
int[,] data = new int[n, m];
for (int i = 0; i < n; i++)
{
for (int j = 0; j < m; j++)
{
Console.WriteLine("please enter a new value");
int number;
number = Int32.Parse(Console.ReadLine());
data[i, j] = number;
}
}
return data;
}
static void SumOfPlatform(int[,] data)
{
int sum =0;
int x = 0;
int y = 0;
int maxSum = 0;
for (int i = 0; i < data.GetLength(0) - 2; i++)
{
for (int j = 0; j < data.GetLength(1) - 2; j++)
{
for (int k = 0; k < 3; k++)
{
for (int l = 0; l < 3; l++)
{
sum =+ data[i + k, j + l];
}
}
if (maxSum < sum)
{
maxSum = sum;
x = i;
y = j;
}
sum =0;
}
}
Console.WriteLine("Sum: {0}\nPosition: {1} {2}",maxSum,x,y );
}
static void Main()
{
int[,] data = ArrayReadConsole();
SumOfPlatform(data);
}
}
}
I wrote that code but something went wrong... It doesn't find position or sum of the matrix I enter. I know that 4x for loop is a bad idea just I didn't want to make another method just for that. Any idea why it doesn't work?
Your Code for SumOfPlatform is working with only change from =+ to +=
static void SumOfPlatform(int[,] data)
{
int sum = 0;
int x = 0;
int y = 0;
int maxSum = 0;
for (int i = 0; i < data.GetLength(0) - 2; i++)
{
for (int j = 0; j < data.GetLength(1) - 2; j++)
{
for (int k = 0; k < 3; k++)
{
for (int l = 0; l < 3; l++)
{
sum += data[i + k, j + l]; //only Change
}
}
if (maxSum < sum)
{
maxSum = sum;
x = i;
y = j;
}
sum = 0;
}
}
Console.WriteLine("Sum: {0}\nPosition: {1} {2}", maxSum, x, y);
}
static void Main(string[] args)
{
// int[,] data = ArrayReadConsole();
int[,] data = new int[,]
{
{1,4,6,7,3,5,7,4 },
{1,4,5,3,3,5,4,4 },
{1,1,6,2,1,5,7,4 },
{1,3,6,3,3,5,2,4 },
{1,4,6,2,3,5,3,4 },
{1,4,2,2,3,5,3,4 },
{1,4,3,3,3,5,2,4 },
{1,4,4,3,3,5,2,4 }
};
SumOfPlatform(data);
}
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();
}
}
}