Add utility for solve: factorize and solve in one function

Author: termoshtt

examples/solve.rs

@@ -5,17 +5,26 @@ extern crate ndarray_linalg;
 use ndarray::*;
 use ndarray_linalg::*;
 
+// Solve `Ax=b`
+fn solve() -> Result<(), error::LinalgError> {
+    let a: Array2<f64> = random((3, 3));
+    let b: Array1<f64> = random(3);
+    let _x = a.solve(&b)?;
+    Ok(())
+}
+
 // Solve `Ax=b` for many b with fixed A
 fn factorize() -> Result<(), error::LinalgError> {
     let a: Array2<f64> = random((3, 3));
     let f = a.factorize_into()?; // LU factorize A (A is consumed)
     for _ in 0..10 {
         let b: Array1<f64> = random(3);
-        let _x = f.solve(&b)?; // solve Ax=b using factorized L, U
+        let _x = f.solve_into(b)?; // solve Ax=b using factorized L, U
     }
     Ok(())
 }
 
 fn main() {
+    solve().unwrap();
     factorize().unwrap();
 }

src/solve.rs

@@ -101,6 +101,34 @@ where
     }
 }
 
+impl<A, S> Solve<A> for ArrayBase<S, Ix2>
+where
+    A: Scalar,
+    S: Data<Elem = A>,
+{
+    fn solve_mut<'a, Sb>(&self, mut rhs: &'a mut ArrayBase<Sb, Ix1>) -> Result<&'a mut ArrayBase<Sb, Ix1>>
+    where
+        Sb: DataMut<Elem = A>,
+    {
+        let f = self.factorize()?;
+        f.solve_mut(rhs)
+    }
+    fn solve_t_mut<'a, Sb>(&self, mut rhs: &'a mut ArrayBase<Sb, Ix1>) -> Result<&'a mut ArrayBase<Sb, Ix1>>
+    where
+        Sb: DataMut<Elem = A>,
+    {
+        let f = self.factorize()?;
+        f.solve_t_mut(rhs)
+    }
+    fn solve_h_mut<'a, Sb>(&self, mut rhs: &'a mut ArrayBase<Sb, Ix1>) -> Result<&'a mut ArrayBase<Sb, Ix1>>
+    where
+        Sb: DataMut<Elem = A>,
+    {
+        let f = self.factorize()?;
+        f.solve_h_mut(rhs)
+    }
+}
+
 impl<A, S> Factorized<S>
 where
     A: Scalar,