Use f64 instead.

src/matrix.rs

@@ -1,6 +1,6 @@
 use std::ops;
 
-fn det(m: &[f32], x: usize) -> f32 {
+fn det(m: &[f64], x: usize) -> f64 {
     if x == 1 {
         m[0]
     } else if x == 2 {
@@ -17,7 +17,7 @@ fn det(m: &[f32], x: usize) -> f32 {
                 .map(|(_, v)| *v)
                 .collect::<Vec<_>>();
 
-            d += (-1.0f32).powi(n as i32) * m[n] * det(&ms, x - 1);
+            d += (-1.0f64).powi(n as i32) * m[n] * det(&ms, x - 1);
         }
 
         d
@@ -26,7 +26,7 @@ fn det(m: &[f32], x: usize) -> f32 {
 
 #[derive(Clone, Debug)]
 pub struct Matrix {
-    data: Box<[f32]>,
+    data: Box<[f64]>,
     height: usize,
     width: usize,
 }
@@ -80,7 +80,7 @@ impl Matrix {
         matrix
     }
 
-    pub fn determinant(&self) -> f32 {
+    pub fn determinant(&self) -> f64 {
         debug_assert!(self.width == self.height);
 
         det(&self.data, self.width)
@@ -122,7 +122,7 @@ impl Matrix {
 }
 
 impl ops::Index<(usize, usize)> for Matrix {
-    type Output = f32;
+    type Output = f64;
 
     fn index(&self, pos: (usize, usize)) -> &Self::Output {
         &self.data[(self.width * pos.0) + pos.1]
@@ -135,7 +135,7 @@ impl ops::IndexMut<(usize, usize)> for Matrix {
     }
 }
 
-impl<'a> ops::Mul<&'a Matrix> for f32 {
+impl<'a> ops::Mul<&'a Matrix> for f64 {
     type Output = Matrix;
 
     fn mul(self, rhs: &'a Matrix) -> Matrix {