i need to write a program that takes 1 to 100 integers randomly, then i need to take this program's transpose, then I need to sort this matrix (each row in itself) from smallest to largest.
and finally, i need to find this matrix's peak value. here is what i have written for the program. for now, it creates a random matrix (20x5) and then it takes its transpose. can you help me with finding its peak value and then sort its each row?
PS.: using classes is mandatory!
using System;
namespace my_matrix;
class Program
{
public int[,] Create(int[,] myarray, int Row, int Clm)
{
Random value = new Random();
myarray = new int[Row, Clm];
int i = 0;
int j = 0;
while (i < Row)
{
while (j < Clm)
{
myarray[i, j] = value.Next(1, 100);
j++;
}
i++;
j = 0;
}
return myarray;
}
public int[,] Print(int[,] myarray, int Row, int Clm)
{
Console.WriteLine("=====ARRAY=====");
for (int a = 0; a < Row; a++)
{
for (int b = 0; b < Clm; b++)
{
Console.Write(myarray[a, b] + " ");
}
Console.WriteLine();
}
return null;
}
public int[,] Transpose(int[,] myarray, int Row, int Clm)
{
for (int b = 0; b < Clm; b++)
{
for (int a = 0; a < Row; a++)
{
Console.Write(myarray[a, b] + " ");
}
Console.WriteLine();
}
return myarray;
}
public int[,] Print_Transpose(int[,] myarray, int Row, int Clm)
{
Console.WriteLine("=====TRANSPOSE=====");
for (int b = 0; b < Clm; b++)
{
for (int a = 0; a < Row; a++)
{
Console.Write(myarray[a, b] + " ");
}
Console.WriteLine();
}
return null;
}
static void Main(string[] args)
{
Program x = new Program();
int[,] myarray = new int[20, 5];
int[,] a = x.Create(myarray, 20, 5);
x.Print(a, 20, 5);
x.Print_Transpose(a, 20, 5);
}
}
i don't know how to make a class which sorta each row from smallest to largest and also i dont know how to create a class which finds the matrix's peak value.
You can run over the array, keeping the maxNum:
public int getMax(int[,] fromArray)
{
int maxNum = 0;
for (int b = 0; b < fromArray.GetUpperBound(1); b++)
{
for (int a = 0; a < fromArray.GetUpperBound(0); a++)
{
if (maxNum < fromArray[a,b])
{
maxNum = fromArray[a, b];
}
}
}
return maxNum;
}
Call the function like:
Console.Write("Max number = {0:D}", x.getMax (a));
If you want a sort method, you can place all values in a List, sort them and convert back to array.
public int[] SortArray(int[,] fromArray)
{
List<int> newList = new List<int>(fromArray.Length);
for (int b = 0; b < fromArray.GetUpperBound(1); b++)
{
for (int a = 0; a < fromArray.GetUpperBound(0); a++)
{
newList.Add (fromArray[a, b]);
}
}
newList.Sort();
return newList.ToArray<int>();
}
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();
}
}
}
The following code sorts rows by the first element using bubble method.
I can't change it to counting sort.
public void SortStack(double[,] n)
{
for (int i = 0; i < n.GetLength(0) - 1; i++)
{
for (int j = i; j < n.GetLength(0); j++)
{
if (n[i, 0] > n[j, 0])
{
for (int k = 0; k < n.GetLength(1); k++)
{
var temp = n[i, k];
n[i, k] = n[j, k];
n[j, k] = temp;
}
}
}
}
}
Please help.
As you do bubble sort based on first element of each row. you should do counting sort like that too. so you just need to count first item of each row.
private static int[,] CountingSort2D(int[,] arr)
{
// find the max number by first item of each row
int max = arr[0, 0];
for (int i = 0; i < arr.GetLength(0); i++)
{
if (arr[i, 0] > max) max = arr[i, 0];
}
// we want to get count of first items of each row. thus we need 1d array.
int[] counts = new int[max + 1];
// do the counting. again on first index of each row
for (int i = 0; i < arr.GetLength(0); i++)
{
counts[arr[i, 0]]++;
}
for (int i = 1; i < counts.Length; i++)
{
counts[i] += counts[i - 1];
}
// result is sorted array
int[,] result = new int[arr.GetLength(0), arr.GetLength(1)];
for (int i = arr.GetLength(0) - 1; i >= 0; i--)
{
counts[arr[i, 0]]--;
// now we need to copy columns too. thus we need another loop
for (int j = 0; j < arr.GetLength(1); j++)
{
result[counts[arr[i, 0]], j] = arr[i, j];
}
}
return result;
}
Here is the test.
static void Main()
{
Random rand = new Random();
int[,] arr = new int[3,3];
for (int i = 0; i < 3; i++)
{
for (int j = 0; j < 3; j++)
{
arr[i, j] = rand.Next(0, 100);
}
}
int[,] newarr = CountingSort2D(arr);
for (int i = 0; i < arr.GetLength(0); i++)
{
Console.Write("{ ");
for (int j = 0; j < arr.GetLength(1); j++)
{
Console.Write(arr[i, j] + " ,");
}
Console.Write("} ,");
}
Console.WriteLine();
for (int i = 0; i < newarr.GetLength(0); i++)
{
Console.Write("{ ");
for (int j = 0; j < newarr.GetLength(1); j++)
{
Console.Write(newarr[i, j] + " ,");
}
Console.Write("} ,");
}
Console.WriteLine();
}
Example Output:
{ 49,66,8 },{ 33,39,64 },{ 65,52,76 } // Original array
{ 33,39,64 },{ 49,66,8 },{ 65,52,76 } // Sorted array
I have a 2D array of integers which stores only values [1,0] as shown below.
int[,] INPUT = new int[10, 10] {
{1,1,0,0,0,1,1,1,0,0},
{1,0,0,0,1,0,0,0,1,0},
{0,0,0,1,1,0,0,1,0,1},
{1,1,0,0,0,0,0,1,1,0},
{0,1,0,0,0,1,0,1,1,0},
{0,0,0,0,1,0,1,0,0,0},
{1,0,0,1,0,0,1,1,1,0},
{0,1,0,0,1,1,0,0,1,1},
{0,1,1,1,0,1,0,1,1,0},
{0,0,0,0,0,1,1,0,0,0},
};
I need to identify a Colony count for the input image, where a Colony is defined as a contiguous sequence of 1s (Like in this array, there are 3 colony of 1's). Connection between 1s can be either adjacent or on the diagonal.
I am required to use recursion for this.
class Program
{
public static int count;
public static int colony;
public static int[,] INPUT;
public static int rows = 10;
public static int cols = 10;
static void Main(string[] args)
{
int[,] INPUT = new int[10, 10] {
{1,1,0,0,0,1,1,1,0,0},
{1,0,0,0,1,0,0,0,1,0},
{0,0,0,1,1,0,0,1,0,1},
{1,1,0,0,0,0,0,1,1,0},
{0,1,0,0,0,1,0,1,1,0},
{0,0,0,0,1,0,1,0,0,0},
{1,0,0,1,0,0,1,1,1,0},
{0,1,0,0,1,1,0,0,1,1},
{0,1,1,1,0,1,0,1,1,0},
{0,0,0,0,0,1,1,0,0,0},
};
// Showing All Values From Upper 2D array
Console.WriteLine("Input File Contain: \n");
for (int i = 0; i < rows; i++)
{
for (int j = 0; j < cols; j++)
{
Console.Write(INPUT[i, j]);
}
Console.WriteLine();
}
// Getting Total 1's Count Only
for (int i = 0; i < rows; i++)
{
for (int j = 0; j < cols; j++)
{
if (INPUT[i, j] == 1)
{
count = count + 1;
}
}
Console.WriteLine();
}
// Getting Total 1's Colony Only
for (int i = 0; i < rows; i++)
{
for (int j = 0; j < cols; j++)
{
if (INPUT[i, j] == 1)
{
INPUT[i, j] = 0;
colony = GetColony(i, j);
}
}
}
Console.WriteLine("Counts Of 1 Are: " + count);
Console.WriteLine("Counts Of 1's Colony Are: " + colony );
}
static public int GetColony(int i, int j)
{
if ((i < rows) && (j < cols))
{
if ((INPUT[i - 1, j] == 1) || (INPUT[i + 1, j] == 1) || (INPUT[i, j - 1] == 1) || (INPUT[i, j + 1] == 1))
{
INPUT[i, j] = 0;
return GetColony(i, j);
}
else
{
return 1;
}
}
else
{
return 1;
}
}
}
I want write extension method for fill multidimensional rectangular array. I know how to do it for the array with a fixed number of measurements:
public static void Fill<T>(this T[] source, T value)
{
for (int i = 0; i < source.Length; i++)
source[i] = value;
}
public static void Fill<T>(this T[,] source, T value)
{
for (int i = 0; i < source.GetLength(0); i++)
for (int j = 0; j < source.GetLength(1); j++)
source[i, j] = value;
}
public static void Fill<T>(this T[,,] source, T value)
{
for (int i = 0; i < source.GetLength(0); i++)
for (int j = 0; j < source.GetLength(1); j++)
for (int k = 0; k < source.GetLength(2); k++)
source[i, j, k] = value;
}
Can I write one fill-method for all multidimensional rectangular array?
You can change the fixed dimension parameter to an Array parameter so you can put the extension on any Array. Then I used recursion to iterate through each position of the array.
public static void Fill<T>(this Array source, T value)
{
Fill(0, source, new long[source.Rank], value);
}
static void Fill<T>(int dimension, Array array, long[] indexes, T value)
{
var lowerBound = array.GetLowerBound(dimension);
var upperBound = array.GetUpperBound(dimension);
for (int i = lowerBound; i <= upperBound; i++)
{
indexes[dimension] = i;
if (dimension < array.Rank - 1)
{
Fill(dimension + 1, array, indexes, value);
}
else
{
array.SetValue(value, indexes);
}
}
}
Here's a solution that does not use recursion (and is less complex):
public static void FillFlex<T>(this Array source, T value)
{
bool complete = false;
int[] indices = new int[source.Rank];
int index = source.GetLowerBound(0);
int totalElements = 1;
for (int i = 0; i < source.Rank; i++)
{
indices[i] = source.GetLowerBound(i);
totalElements *= source.GetLength(i);
}
indices[indices.Length - 1]--;
complete = totalElements == 0;
while (!complete)
{
index++;
int rank = source.Rank;
indices[rank - 1]++;
for (int i = rank - 1; i >= 0; i--)
{
if (indices[i] > source.GetUpperBound(i))
{
if (i == 0)
{
complete = true;
return;
}
for (int j = i; j < rank; j++)
{
indices[j] = source.GetLowerBound(j);
}
indices[i - 1]++;
}
}
source.SetValue(value, indices);
}
}
This is modeled from the System.Array.ArrayEnumerator. This implementation should have a similar level of correctness as ArrayEnumerator and (based on a few spot checks) appears to function fine.