little Bug

[miguemorales]

I have found your code very useful for a project where i use simple Matrix, but i have found a little bug in the determinant calculation, i attach you the code solving this error:
double matDet(Matrix* M) {
Matrix* Copy;
Copy = matCopy(M);
double det, factor;
if (M->columns != M->rows) {
printf("Columns and rows must have same length");
return -1;
}
else if (M->columns ==2){
det = Copy->numbers[0][0]*Copy->numbers[1][1]-Copy->numbers[0][1]*Copy->numbers[1][0];
return det;
}
det = 0;
for (int i = 0; i < Copy->columns; i++) {
Matrix *Submat;
int ncol = Copy->columns-1;
double v = (double)malloc(sizeof(double)ncolncol);
double *cv = v;
unsigned int count;
for (int ii = 0; ii < Copy->columns; ii++){
for ( int jj = 0; jj < Copy->rows; jj++){
if (jj != 0 && ii != i){
*v = Copy->numbers[jj][ii];
v ++;
}
}
}
Submat = matCreator(ncol,ncol,cv);
det += matDet(Submat)*Copy->numbers[i][0]*pow(-1,i);
freee(Submat);
}

return det;

}

[nhomble]

thanks @miguemorales for catching an issue. Do you have an example matrix I can use to reproduce? I've slowly been adding tests as bugs arise. And are you interested in create a pr?

[miguemorales]

yes, any matrix that contain zeros in the main diagonal, you can try. what is a pr? im not use to code in git hehe

[nhomble]

oh no worries

1. fork this repo
2. checkout the code to your own machine
3. create the change, push to your fork
4. then github will allow you to create a pull request from your fork to this repo