c: quantum gate and state foundations

1 files changed, 9 insertions, 0 deletions

diff --git a/src/maths/matrix.c b/src/maths/matrix.c
index 400c2a7..44b953c 100644
--- a/src/maths/matrix.c
+++ b/src/maths/matrix.c
@@ -30,6 +30,15 @@ struct PsiMatrix psi_clone_matrix(struct PsiMatrix m)
 	return psi_new_matrix_from(m.data, m.rows, m.cols);
 }
 
+struct PsiMatrix psi_identity_matrix(size_t size)
+{
+	struct PsiMatrix m = psi_new_matrix(size, size);
+	for (size_t i = 0; i < size; i++)
+		m.data[i * size + i] = psi_new_complex(1.0, 0.0);
+
+	return m;
+}
+
 void psi_free_matrix(struct PsiMatrix *m)
 {
 	free(m->data);