Add Vector.insert (similar to Matrix.InsertColumn and Matrix.InsertRow)

src/FSharp/Vector.fs

@@ -32,6 +32,7 @@ namespace MathNet.Numerics.LinearAlgebra.Double
 
 open MathNet.Numerics.LinearAlgebra
 open MathNet.Numerics.LinearAlgebra.Generic
+
 /// A module which implements functional vector operations.
 module Vector =
         
@@ -173,4 +174,14 @@ module Vector =
         let mutable p = v.Item(v.Count-1)
         for i=2 to v.Count do
             p <- f (v.Item(v.Count - i)) p
-        p
+        p
+
+    /// Creates a new vector and inserts the given value at the given index.
+    let inline insert index value (v: #Vector<float>) =        
+        let newV = new DenseVector(v.Count + 1)                
+        for i = 0 to index - 1 do 
+            newV.Item(i) <- v.Item(i)        
+        newV.Item(index) <- value        
+        for i = index + 1 to v.Count do 
+            newV.Item(i) <- v.Item(i - 1)        
+        newV

src/FSharpUnitTests/Program.fs

@@ -96,6 +96,8 @@ let VectorTests =
             (Vector.reduce (fun acc x -> acc ** x) smallv |> should approximately_equal 14 0.990295218585507)
         spec "Vector.reduceBack"
             (Vector.reduceBack (fun x acc -> x ** acc) smallv |> should approximately_equal 14 0.488911287726319)
+        spec "Vector.insert"
+            (Vector.insert 2 0.5 smallv |> should approximately_vector_equal 14 (new DenseVector ( [|0.3;0.3;0.5;0.3;0.3;0.3|] ) :> Vector<float>) )
     ]