matrix multiplication in C - structures used

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I've searched for a similar situation but have drawn a blank so I'm posting my problem here:

void mtxmulti(struct matrix mAx, struct matrix mBx) {
struct matrix mCx;
printf("A * B:\n");
if ((mAx.nrows == mBx.nrows) && (mAx.ncols == mBx.ncols)) {
    for (mAx.row = 0, mBx.row; mAx.row < mAx.nrows, mBx.row < mBx.nrows; mAx.row++, mBx.row++) {
        for (mAx.col = 0, mBx.col; mAx.col < mAx.ncols, mBx.col < mBx.ncols; mAx.col++, mBx.col++) {
            mCx.matrix[mCx.row][mCx.col] += mAx.matrix[mAx.row][mAx.col] * mBx.matrix[mBx.row][mAx.col];
        }
    }
    mtxpr1t(mCx); /*If successful, prints the matrix*/
}

What you see here is my function to multiply two matrices together, however it crashes when I try to run it. I'm being told that 'mCx' is uninitialized and because of this won't work.

Other useful parts of the code:

struct matrix {
int** matrix;
int row, col, nrows, ncols;
};
int main(void) {
struct matrix A, B;
printf("Enter the number of rows and columns for A: ");
scanf("%d %d", &A.nrows, &A.ncols);
A.matrix = alloc(A.nrows, A.ncols); /*Allocates array*/
. /*This part of code is 
. just entering the values 
. of the matrix*/ 
printf("Enter the number of rows and columns for B: ");
scanf("%d %d", &A.nrows, &B.ncols);
A.matrix = alloc(A.nrows, A.ncols); /*Allocates array*/
. /*This part of code is 
. just entering the values 
. of the matrix*/
}

FYI: I hadn't needed to initialize matrix A and B, although I did allocate space for them as seen in the section above.

asked 3 mins ago

Kristopher Rahim Afful-Brown

6

matrix multiplication in C - structures used