Matrix Problem

[owCSLyTq]

Hello, i'm having trouble with the cofactors while compiling. can you tell me the problem?

#include<iostream>
using namespace std;

int main()
{
int add(int matA[3][3],int matB[3][3]);
int sub(int matA[3][3],int matB[3][3]);
int mul(int matA[3][3],int matB[3][3]);
int Tr(int matA[3][3]);
int det(int matA[3][3]);
int Trans(int matA[3][3]);
int cofactor(int mat[3][3]);
int inv(int matA[3][3]);
int solve(int matA[3][3],int b[3]);

int x,A[3][3],B[3][3],b[3],C[3][3];
cout<<"This program allows you to perform certain matrix and vector operations on a 3x3 matrix"<<endl;
cout<<"If you wish to add two matrices, subtract one matrix from another one, multiply two matrices, calculate the trace, the determinant, transpose, adjoint, inverse or solve a linear system of equations, press 1,2,3,4,5,6,7,8 or 9, respectively";

cin>>x;
switch(x){

case 1:
	{
cout<<"enter matrix 1";
cin>>A[3][3];
cout<<"enter matrix 2";
cin>>B[3][3];
cout<<"the sum is "<<add(A,B);
	break;
	}
case 2:
	{
cout<<"enter matrix 1";
cin>>A[3][3];
cout<<"enter matrix 2";
cin>>B[3][3];
cout<<"the difference is"<<sub(A,B);
	break;
	}
case 3:
	{
cout<<"enter matrix 1";
cin>>A[3][3];
cout<<"enter matrix 2";
cin>>B[3][3];
cout<<"the product is"<<mul(A,B);
	break;
	}
case 4:
	{
cout<<"enter your matrix";
cin>>A[3][3];
cout<<"the trace is "<<Tr(A);
	break;
	}
case 5:
	{
cout<<"enter your matrix";
cin>>A[3][3];
cout<<"the determinant is"<<det(A);
	break;
	}
case 6:
	{
cout<<"Enter your matrix";
cin>>A[3][3];
cout<<"The transpose is"<<Trans(A);
	break;
	}
case 7:
	{
cout<<"Enter your matrix";
cin>>A[3][3];
cout<<"The adjoint is"<<Trans(cofactor(A));
	break;
	}
case 8:
	{
cout<<"Enter your matrix";
cin>>A[3][3];
cout<<"The inverse is"<<inv(A);
	break;
	}
case 9:
	{
cout<<"Do you want to solve an equation in the form Ax=b?" <<endl;
cout<<"Enter your matrix A";
cin >>A[3][3];
cout<<"Enter your vector b";
cin>>b[3];
cout<<"The solution is"<<inv(A)*b[3];
	break;
	}

default:
	{
cout<<"Choose a number between 1 and 9 inclusive";
	}
}


int add(int matA[3][3],int matB[3][3]);
{
for(int i=0;i<3;i++)
{
for(int j=0;j<3;j++)
{
return A[i][j]+B[i][j];
}
}
}
	
int sub(int matA[3][3],int matB[3][3]);
{
for (int i=0;i<3;i++)
{
for(int j =0;j<3;j++)
{
return A[i][j]-B[i][j];
}
}
}

int mul (int matA[3][3],int matB[3][3],int matC[3][3]);
{
	int i;int j;int k;
	
for (int i=0; i<3;i++)
for (int j=0;j<3;j++)
for (int k=0;k<3;k++)
C[i][j]=0;
C[i][j]+=A[i][k]*B[k][j];
{
return C[i][j]; 
}
}

int Tr(int matA[3][3]);
{ return A[0][0]+A[1][1]+A[2][2];

}

int det(int matA[3][3]);
{
	return  (A[0][0]*((A[1][1]*A[2][2])-(A[1][2]*A[2][1])))-(A[0][1]*((A[1][0]*A[2][2])-(A[1][2]*A[2][0]))+(A[0][2]*((A[1][0]*A[2][1])-(A[1][1]*A[2][0]))));

}

int Trans(int matA[3][3]);
{
int i;int j;
for (int i=0;i<3;i++)
 for(int j=0;j<3;j++)
B[i][j]=A[j][i];
return B[i][j];
}


int cofactor(int matB[3][3]);
{
	return;
	{

	C[0][0]=B[1][1]*B[2][2]-B[2][1]*B[1][2];
	C[0][1]=-(B[1][0]*B[2][2]-B[2][0]*B[1][2]);
	C[0][2]=B[1][0]*B[2][1]-B[2][0]*B[1][1];
	C[1][0]=-(B[0][1]*B[2][2]-B[2][1]*B[0][2]);
	C[1][1]=B[0][0]*B[2][2]-B[2][0]*B[0][2];
	C[1][2]=-(B[0][0]*B[2][1]-B[2][0]*B[0][1]);
	C[2][0]=B[0][1]*B[1][2]-B[1][1]*B[0][2];
	C[2][1]=-(B[0][0]*B[1][2]-B[1][0]*B[1][2]);
	C[2][2]=B[0][0]*B[1][1]-B[1][0]*B[0][1];

}

}
int inv(int matA[3][3]);
{if (det<=0)
	cout<<"the inverse does not exist";
	else return (Trans(cofactor(A)))/det;
}


int solve(int matA[3][3],int vectb[3]);
{
	return inv(A)*b[3];
}
system("PAUSE");
}

[ingenioushax]

Does return; in your cofactor method make sense? SHould their be a semicolon after return if you're trying to return a value?

[keskiverto]

i'm having trouble while compiling

A compiler error? What error?

[owCSLyTq]

cout<<"The adjoint is"<<Trans(cofactor(A));

1>g:\matrix project.cpp(75): error C2664: 'Trans' : cannot convert parameter 1 from 'int' to 'int [][3]'


the return; in cofactor and the int main() above are causing the errors when debugging and i don't see how to solve it.

[keskiverto]

You claim that cofactor() returns an int. It probably should not. Define it as:
void cofactor( int matB[3][3], int matC[3][3] )

Then you obviously need a int [3][3] that you pass to cofactor() and Trans().

Do not declare functions inside main(). Do it before main().

[owCSLyTq]

what do you mean that "Then you obviously need a int [3][3] that you pass to cofactor() and Trans()."

Thanks :)

[keskiverto]

Lets ignore that for now.

Given that you have int A[3][3];, what does this piece of your code do?
cin>>A[3][3];

[owCSLyTq]

It's a 3x3 array to find matrix A.

[keskiverto]

The cin>>A[3][3]; ?

That statement extracts one integer from input stream object 'cin' and stores it into memory location at A+9. Too bad the matrix referred to by name 'A' covers only locations from A to A+8. We have no idea what is in A+9, i.e. what does that statement accidentally overwrite.

These Fora have several recent threads about reading data into (2D) arrays. Browse some.

[owCSLyTq]

I wrote another program today. But now I can find a solution to how to solve the linear problem. It keep saying break continue.