'matrix' containing an integer matrix as a member and method

Try this:

using System;

class Matrix

{

private int[,] _matrix;

public int Rows { get { return _matrix.GetLength(0); } }

public int Cols { get { return _matrix.GetLength(1); } }

public int this[int row, int col]

{

get { return _matrix[row, col]; }

set { _matrix[row, col] = value; }

}

public Matrix(int rows, int cols)

{

_matrix = new int[rows, cols];

}

public void Fill()

{

Console.WriteLine("Enter elements of each row separated by spaces\n");

for(int i = 0; i < this.Rows; i++)

{

Console.Write(" Row {0} : ", i + 1);

string input = Console.ReadLine();

string[] elements = input.Split(new char[]{' '}, StringSplitOptions.RemoveEmptyEntries);

if (elements.Length != this.Cols)

{

Console.WriteLine("There must be exactly {0} columns, try again", this.Cols);

--i;

}

else

{

for(int j = 0; j < this.Cols; j++)

{

int.TryParse(elements[j], out _matrix[i,j]);

}

public void Print()

{

for(int i = 0; i < this.Rows; i++)

{

for(int j = 0; j < this.Cols; j++)

{

Console.Write("{0,3} ", _matrix[i,j]);

}

Console.WriteLine();

}

public static Matrix Multiply(Matrix m1, Matrix m2)

{

if(m1.Cols != m2.Rows)

throw new ArgumentException("Matrices cannot be multiplied");

Matrix m3 = new Matrix(m1.Rows, m2.Cols); // all zero by default

for (int i = 0; i < m3.Rows; i++)

{

for (int j = 0; j < m3.Cols; j++)

{

for (int k = 0; k < m1.Cols; k++)

{

m3[i, j] += m1[i, k] * m2[k, j];

}

return m3;

}

class Program

{

static void Main()

{

int rows1;

{

Console.Write("Enter number of rows for matrix 1 : ");

int.TryParse(Console.ReadLine(), out rows1);

}

while(rows1 < 1);

int cols1;

{

Console.Write("Enter number of cols for matrix 1 : ");

int.TryParse(Console.ReadLine(), out cols1);

}

while(cols1 < 1);

var m1 = new Matrix(rows1, cols1);

m1.Fill();

Console.WriteLine();

int rows2;

{

Console.Write("Enter number of rows for matrix 2 : ");

int.TryParse(Console.ReadLine(), out rows2);

}

while(rows2 < 1);

int cols2;

{

Console.Write("Enter number of cols for matrix 2 : ");

int.TryParse(Console.ReadLine(), out cols2);

}

while(cols2 < 1);

var m2 = new Matrix(rows2, cols2);

m2.Fill();

Matrix m3 = Matrix.Multiply(m1, m2);

Console.WriteLine("\nPrinting matrix 1 ...\n");

m1.Print();

Console.WriteLine("\nPrinting matrix 2 ...\n");

m2.Print();

Console.WriteLine("\nPrinting matrix 3 ...\n");

m3.Print();

Console.ReadKey(true);

}

Sample input and output:

Enter number of rows for matrix 1 : 2

Enter number of cols for matrix 1 : 4

Enter elements of each row separated by spaces

Row 1 : 1 3 5 7

Row 2 : 2 4 6 8

Enter number of rows for matrix 2 : 4

Enter number of cols for matrix 2 : 3

Enter elements of each row separated by spaces

Row 1 : 1 8 9

Row 2 : 2 7 10

Row 3 : 3 6 11

Row 4 : 4 5 12

Printing matrix 1 ...

1 3 5 7

2 4 6 8

Printing matrix 2 ...

1 8 9

2 7 10

3 6 11

4 5 12

Printing matrix 3 ...

50 94 178

60 120 220

1 Reply

Know the answer? Post it — somebody with the same question will find it here.

Vulpes11y ago
Try this:

using System;

class Matrix
{
private int[,] _matrix;

public int Rows { get { return _matrix.GetLength(0); } }
public int Cols { get { return _matrix.GetLength(1); } }

public int this[int row, int col]
{
get { return _matrix[row, col]; }
set { _matrix[row, col] = value; }
}

public Matrix(int rows, int cols)
{
_matrix = new int[rows, cols];
}

public void Fill()
{
Console.WriteLine("Enter elements of each row separated by spaces\n");

for(int i = 0; i < this.Rows; i++)
{
Console.Write(" Row {0} : ", i + 1);
string input = Console.ReadLine();
string[] elements = input.Split(new char[]{' '}, StringSplitOptions.RemoveEmptyEntries);
if (elements.Length != this.Cols)
{
Console.WriteLine("There must be exactly {0} columns, try again", this.Cols);
--i;
}
else
{
for(int j = 0; j < this.Cols; j++)
{
int.TryParse(elements[j], out _matrix[i,j]);
}
}
}
}

public void Print()
{
for(int i = 0; i < this.Rows; i++)
{
for(int j = 0; j < this.Cols; j++)
{
Console.Write("{0,3} ", _matrix[i,j]);
}

Console.WriteLine();
}
}

public static Matrix Multiply(Matrix m1, Matrix m2)
{
if(m1.Cols != m2.Rows)
throw new ArgumentException("Matrices cannot be multiplied");

Matrix m3 = new Matrix(m1.Rows, m2.Cols); // all zero by default

for (int i = 0; i < m3.Rows; i++)
{
for (int j = 0; j < m3.Cols; j++)
{
for (int k = 0; k < m1.Cols; k++)
{
m3[i, j] += m1[i, k] * m2[k, j];
}
}
}

return m3;
}
}

class Program
{
static void Main()
{
int rows1;

do
{
Console.Write("Enter number of rows for matrix 1 : ");
int.TryParse(Console.ReadLine(), out rows1);
}
while(rows1 < 1);

int cols1;

do
{
Console.Write("Enter number of cols for matrix 1 : ");
int.TryParse(Console.ReadLine(), out cols1);
}
while(cols1 < 1);

var m1 = new Matrix(rows1, cols1);
m1.Fill();
Console.WriteLine();

int rows2;

do
{
Console.Write("Enter number of rows for matrix 2 : ");
int.TryParse(Console.ReadLine(), out rows2);
}
while(rows2 < 1);

int cols2;

do
{
Console.Write("Enter number of cols for matrix 2 : ");
int.TryParse(Console.ReadLine(), out cols2);
}
while(cols2 < 1);

var m2 = new Matrix(rows2, cols2);
m2.Fill();

Matrix m3 = Matrix.Multiply(m1, m2);

Console.WriteLine("\nPrinting matrix 1 ...\n");
m1.Print();

Console.WriteLine("\nPrinting matrix 2 ...\n");
m2.Print();

Console.WriteLine("\nPrinting matrix 3 ...\n");
m3.Print();

Console.ReadKey(true);
}
}

Sample input and output:

Enter number of rows for matrix 1 : 2
Enter number of cols for matrix 1 : 4
Enter elements of each row separated by spaces

Row 1 : 1 3 5 7
Row 2 : 2 4 6 8

Enter number of rows for matrix 2 : 4
Enter number of cols for matrix 2 : 3
Enter elements of each row separated by spaces

Row 1 : 1 8 9
Row 2 : 2 7 10
Row 3 : 3 6 11
Row 4 : 4 5 12

Printing matrix 1 ...

1 3 5 7
2 4 6 8

Printing matrix 2 ...

1 8 9
2 7 10
3 6 11
4 5 12

Printing matrix 3 ...

50 94 178
60 120 220