From 89a5136191522a2882ffa3f8a10bda92161024b5 Mon Sep 17 00:00:00 2001
From: morenol <morenoluisma@gmail.com>
Date: Wed, 25 Nov 2020 14:39:02 -0400
Subject: [PATCH] Change implementation of to_row_vector for nalgebra (#34)

* Add failing test

* Change implementation of to_row_vector for nalgebra
---
 Cargo.toml                       |  4 ++--
 src/linalg/naive/dense_matrix.rs |  6 ++++++
 src/linalg/nalgebra_bindings.rs  | 11 +++++++++--
 src/linalg/ndarray_bindings.rs   |  6 ++++++
 4 files changed, 23 insertions(+), 4 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index 20eebf5..6e15f88 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -20,7 +20,7 @@ datasets = []
 
 [dependencies]
 ndarray = { version = "0.13", optional = true }
-nalgebra = { version = "0.22.0", optional = true }
+nalgebra = { version = "0.23.0", optional = true }
 num-traits = "0.2.12"
 num = "0.3.0"
 rand = "0.7.3"
@@ -35,4 +35,4 @@ bincode = "1.3.1"
 
 [[bench]]
 name = "distance"
-harness = false
\ No newline at end of file
+harness = false
diff --git a/src/linalg/naive/dense_matrix.rs b/src/linalg/naive/dense_matrix.rs
index 7486329..9279c3c 100644
--- a/src/linalg/naive/dense_matrix.rs
+++ b/src/linalg/naive/dense_matrix.rs
@@ -1064,6 +1064,12 @@ mod tests {
         );
     }
 
+    #[test]
+    fn col_matrix_to_row_vector() {
+        let m: DenseMatrix<f64> = BaseMatrix::zeros(10, 1);
+        assert_eq!(m.to_row_vector().len(), 10)
+    }
+
     #[test]
     fn iter() {
         let vec = vec![1., 2., 3., 4., 5., 6.];
diff --git a/src/linalg/nalgebra_bindings.rs b/src/linalg/nalgebra_bindings.rs
index 8ddfdb6..da2ec05 100644
--- a/src/linalg/nalgebra_bindings.rs
+++ b/src/linalg/nalgebra_bindings.rs
@@ -185,14 +185,15 @@ impl<T: RealNumber + 'static> BaseVector<T> for MatrixMN<T, U1, Dynamic> {
 impl<T: RealNumber + Scalar + AddAssign + SubAssign + MulAssign + DivAssign + Sum + 'static>
     BaseMatrix<T> for Matrix<T, Dynamic, Dynamic, VecStorage<T, Dynamic, Dynamic>>
 {
-    type RowVector = MatrixMN<T, U1, Dynamic>;
+    type RowVector = RowDVector<T>;
 
     fn from_row_vector(vec: Self::RowVector) -> Self {
         Matrix::from_rows(&[vec])
     }
 
     fn to_row_vector(self) -> Self::RowVector {
-        self.row(0).into_owned()
+        let (nrows, ncols) = self.shape();
+        self.reshape_generic(U1, Dynamic::new(nrows * ncols))
     }
 
     fn get(&self, row: usize, col: usize) -> T {
@@ -697,6 +698,12 @@ mod tests {
         assert_eq!(m.to_row_vector(), expected);
     }
 
+    #[test]
+    fn col_matrix_to_row_vector() {
+        let m: DMatrix<f64> = BaseMatrix::zeros(10, 1);
+        assert_eq!(m.to_row_vector().len(), 10)
+    }
+
     #[test]
     fn get_row_col_as_vec() {
         let m = DMatrix::from_row_slice(3, 3, &[1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0]);
diff --git a/src/linalg/ndarray_bindings.rs b/src/linalg/ndarray_bindings.rs
index b5058ab..308e355 100644
--- a/src/linalg/ndarray_bindings.rs
+++ b/src/linalg/ndarray_bindings.rs
@@ -563,6 +563,12 @@ mod tests {
         );
     }
 
+    #[test]
+    fn col_matrix_to_row_vector() {
+        let m: Array2<f64> = BaseMatrix::zeros(10, 1);
+        assert_eq!(m.to_row_vector().len(), 10)
+    }
+
     #[test]
     fn add_mut() {
         let mut a1 = arr2(&[[1., 2., 3.], [4., 5., 6.]]);