2 files changed, 54 insertions, 0 deletions
diff --git a/matrix.c b/matrix.c
index 4bcbf88..c04b91b 100644
--- a/matrix.c
+++ b/matrix.c
@@ -121,6 +121,56 @@ Matrix *matrix_copy (const Matrix *mat)
     return tmp;
 }
 
+Matrix *matrix_swap_rows(const Matrix *mat, size_t i, size_t j)
+{
+    Matrix *tmp = matrix_copy(mat);
+
+    for (size_t k = 0; k < mat->n; ++k)
+    {
+        matrix_at(tmp, i, k) = matrix_at(mat, j, k);
+        matrix_at(tmp, j, k) = matrix_at(mat, i, k);
+    }
+
+    return tmp;
+}
+
+void matrix_swap_rows1(Matrix *mat, size_t i, size_t j)
+{
+    double tmp;
+
+    for (size_t k = 0; k < mat->n; ++k)
+    {
+        tmp = matrix_at(mat, i, k);
+        matrix_at(mat, i, k) = matrix_at(mat, j, k);
+        matrix_at(mat, j, k) = tmp;
+    }
+}
+
+Matrix *matrix_swap_cols(const Matrix *mat, size_t i, size_t j)
+{
+    Matrix *tmp = matrix_copy(mat);
+
+    for (size_t k = 0; k < mat->m; ++k)
+    {
+        matrix_at(tmp, k, i) = matrix_at(mat, k, j);
+        matrix_at(tmp, k, j) = matrix_at(mat, k, i);
+    }
+
+    return tmp;
+}
+
+void matrix_swap_cols1(const Matrix *mat, size_t i, size_t j)
+{
+    double x;
+
+    for (size_t k = 0; k < mat->m; ++k)
+    {
+        x = matrix_at(mat, k, i);
+        matrix_at(mat, k, i) = matrix_at(mat, k, j);
+        matrix_at(mat, k, j) = x;
+    }
+}
+
 double matrix_trace(const Matrix *mat)
 {
     assert(matrix_is_square(mat) && "Trace is not defined for non-square matrices");
diff --git a/matrix.h b/matrix.h
index 7c5da78..63f1441 100644
--- a/matrix.h
+++ b/matrix.h
@@ -32,6 +32,10 @@ char *matrix_to_str(const Matrix *mat);
 Matrix *matrix_id(size_t n);
 Matrix *matrix_const(size_t m, size_t n, double x);
 Matrix *matrix_copy (const Matrix *mat);
+Matrix *matrix_swap_rows(const Matrix *mat, size_t i, size_t j);
+void matrix_swap_rows1(Matrix *mat, size_t i, size_t j);
+Matrix *matrix_swap_cols(const Matrix *mat, size_t i, size_t j);
+void matrix_swap_cols1(const Matrix *mat, size_t i, size_t j);
 double matrix_trace(const Matrix *mat);
 Matrix *matrix_transpose(const Matrix *mat);
 Matrix *matrix_add(const Matrix *A, const Matrix *B);