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Minor reworks of cofactor and adjugate

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Soikk 2022-08-31 22:11:59 +02:00
parent d34cf6941b
commit bd25a9380d
2 changed files with 12 additions and 13 deletions
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21
matrix.c
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@ -176,7 +176,7 @@ long double determinant(matrix *m){
} }
} }
matrix *cofactor(matrix *m){ void cofactor(matrix *m){
if(!isSquare(m)){ if(!isSquare(m)){
fprintf(stderr, "Matrix is not square (%dx%d)\n", m->rows, m->cols); fprintf(stderr, "Matrix is not square (%dx%d)\n", m->rows, m->cols);
return NULL; return NULL;
@ -190,7 +190,8 @@ matrix *cofactor(matrix *m){
r->data[i][j] = !((i+j)%2) ? ds : -ds; r->data[i][j] = !((i+j)%2) ? ds : -ds;
} }
} }
return r; copyMatrix(m, r);
freeMatrix(&r);
} }
matrix *transpose(matrix *m){ matrix *transpose(matrix *m){
@ -210,11 +211,11 @@ matrix *dotProduct(matrix *a, matrix *b){
return r; return r;
} }
matrix *adjugate(matrix *m){ void adjugate(matrix *m){
matrix *cm = cofactor(m); cofactor(m);
matrix *r = transpose(cm); matrix *t = transpose(cm);
freeMatrix(&cm); copyMatrix(m, t);
return r; freeMatrix(&t);
} }
void invert(matrix *m){ void invert(matrix *m){
@ -223,10 +224,8 @@ void invert(matrix *m){
fprintf(stderr, "Determinant is 0, the matrix is not invertible\n"); fprintf(stderr, "Determinant is 0, the matrix is not invertible\n");
return; return;
} }
matrix *r = adjugate(m); adjugate(m);
multiplyMatrix(r, 1/d); multiplyMatrix(m, 1/d);
copyMatrix(m, r);
freeMatrix(&r);
} }
void raiseMatrix(matrix *m, int n){ void raiseMatrix(matrix *m, int n){

4
matrix.h
View File

@ -45,13 +45,13 @@ matrix *subMatrix(matrix *m, int row, int col);
long double determinant(matrix *m); long double determinant(matrix *m);
matrix *cofactor(matrix *m); void cofactor(matrix *m);
matrix *transpose(matrix *m); matrix *transpose(matrix *m);
matrix *dotProduct(matrix *a, matrix *b); matrix *dotProduct(matrix *a, matrix *b);
matrix *adjugate(matrix *m); void adjugate(matrix *m);
void invert(matrix *m); void invert(matrix *m);