diff --git a/fractional/src/transform.rs b/fractional/src/transform.rs
index 4ea2a9a..5bfd28e 100644
--- a/fractional/src/transform.rs
+++ b/fractional/src/transform.rs
@@ -19,6 +19,7 @@
// along with this program. If not, see .
//
use std::ops::{Add, Sub, Neg, Mul, Div};
+use std::fmt::Debug;
use crate::Vector;
use crate::trigonometry::Trig;
@@ -28,30 +29,34 @@ pub struct TMatrix( (T, T, T, T)
, (T, T, T, T)
, (T, T, T, T)
, (T, T, T, T) )
- where T: Add + Sub + Neg + Mul + Div + Trig + From + Copy;
+ where T: Add + Sub + Neg + Mul + Div + Debug + Trig + From + Copy;
pub fn unit() -> TMatrix
where T: Add