From 663e2a5fd5cf12b01d10048d0c0848c7ddf1ac99 Mon Sep 17 00:00:00 2001
From: Daniel Vainsencher <daniel.vainsencher@princeton.edu>
Date: Sat, 12 Mar 2016 15:07:08 -0500
Subject: [PATCH 1/3] Add randn to create an array of standard gaussian
 numbers.

---
 Cargo.toml               |  2 +-
 src/impl_constructors.rs | 28 ++++++++++++++++++++++++++++
 2 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/Cargo.toml b/Cargo.toml
index 34150ca00..fc04f58e3 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -36,7 +36,7 @@ optional = true
 
 [dependencies]
 blas-sys = { version = "0.5", optional = true, default-features = false }
-
+rand = "0.3"
 # deprecated! use ndarray-rblas instead
 rblas = { version = "0.0.13", optional = true }
 
diff --git a/src/impl_constructors.rs b/src/impl_constructors.rs
index feb608013..978563ccd 100644
--- a/src/impl_constructors.rs
+++ b/src/impl_constructors.rs
@@ -8,6 +8,9 @@
 
 //! Constructor methods for ndarray
 //!
+extern crate rand;
+use self::rand::distributions::{Normal, IndependentSample};
+use self::rand::{Rng, XorShiftRng, SeedableRng};
 use libnum;
 
 use imp_prelude::*;
@@ -252,3 +255,28 @@ impl<S, A, D> ArrayBase<S, D>
     }
 
 }
+
+use super::NdFloat;
+
+impl<S, A, D> ArrayBase<S, D>
+    where S: DataOwned<Elem=A>,
+          A: NdFloat,
+          D: Dimension,
+{
+    pub fn randn_rng<R: Rng>(dim: D, rng: &mut R) -> ArrayBase<Vec<A>, D>
+    {
+        let size = dim.size_checked().expect("Shape too large: overflow in size");
+        let normal = Normal::new(1.0, 0.0);
+        let iter = (0..size).map(|_| A::from(normal.ind_sample(rng)).unwrap());
+        let arr = OwnedArray::from_iter(iter);
+        arr.into_shape(dim).unwrap()
+    }
+
+    pub fn randn(dim: D) -> ArrayBase<Vec<A>, D>
+    {
+        // Use the thread_rng once to seed a fast, non-crypto grade rng.
+        // To use a crypto quality RNG, use randn_rng directly.
+        let mut rng : XorShiftRng = SeedableRng::from_seed(rand::thread_rng().gen::<[u32;4]>());
+        ArrayBase::<Vec<A>, D>::randn_rng(dim, &mut rng)
+    }
+}

From 589df30e0f387e26efe564515a9e33fb17a9b502 Mon Sep 17 00:00:00 2001
From: Daniel Vainsencher <daniel.vainsencher@princeton.edu>
Date: Sun, 13 Mar 2016 00:07:52 -0500
Subject: [PATCH 2/3] Use asprim crate for a conversion, idimatic weak_rng for
 a seeded XorShift rng.

---
 Cargo.toml               |  1 +
 src/impl_constructors.rs | 11 +++++++----
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index fc04f58e3..c03725d7e 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -36,6 +36,7 @@ optional = true
 
 [dependencies]
 blas-sys = { version = "0.5", optional = true, default-features = false }
+asprim = "0.1"
 rand = "0.3"
 # deprecated! use ndarray-rblas instead
 rblas = { version = "0.0.13", optional = true }
diff --git a/src/impl_constructors.rs b/src/impl_constructors.rs
index 978563ccd..e58d048e0 100644
--- a/src/impl_constructors.rs
+++ b/src/impl_constructors.rs
@@ -10,7 +10,10 @@
 //!
 extern crate rand;
 use self::rand::distributions::{Normal, IndependentSample};
-use self::rand::{Rng, XorShiftRng, SeedableRng};
+use self::rand::{Rng};
+
+extern crate asprim;
+use self::asprim::AsPrim;
 use libnum;
 
 use imp_prelude::*;
@@ -260,14 +263,14 @@ use super::NdFloat;
 
 impl<S, A, D> ArrayBase<S, D>
     where S: DataOwned<Elem=A>,
-          A: NdFloat,
+          A: NdFloat+AsPrim,
           D: Dimension,
 {
     pub fn randn_rng<R: Rng>(dim: D, rng: &mut R) -> ArrayBase<Vec<A>, D>
     {
         let size = dim.size_checked().expect("Shape too large: overflow in size");
         let normal = Normal::new(1.0, 0.0);
-        let iter = (0..size).map(|_| A::from(normal.ind_sample(rng)).unwrap());
+        let iter = (0..size).map(|_| normal.ind_sample(rng).as_());
         let arr = OwnedArray::from_iter(iter);
         arr.into_shape(dim).unwrap()
     }
@@ -276,7 +279,7 @@ impl<S, A, D> ArrayBase<S, D>
     {
         // Use the thread_rng once to seed a fast, non-crypto grade rng.
         // To use a crypto quality RNG, use randn_rng directly.
-        let mut rng : XorShiftRng = SeedableRng::from_seed(rand::thread_rng().gen::<[u32;4]>());
+        let mut rng = rand::weak_rng();
         ArrayBase::<Vec<A>, D>::randn_rng(dim, &mut rng)
     }
 }

From 5e43e0512385b9bd397cdf653b78fb04d49ac4b0 Mon Sep 17 00:00:00 2001
From: Daniel Vainsencher <daniel.vainsencher@princeton.edu>
Date: Mon, 14 Mar 2016 11:40:57 -0400
Subject: [PATCH 3/3] Generalized code and signature to construct arrays with
 different data access.

---
 src/impl_constructors.rs | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/impl_constructors.rs b/src/impl_constructors.rs
index e58d048e0..2e43c39a9 100644
--- a/src/impl_constructors.rs
+++ b/src/impl_constructors.rs
@@ -266,20 +266,20 @@ impl<S, A, D> ArrayBase<S, D>
           A: NdFloat+AsPrim,
           D: Dimension,
 {
-    pub fn randn_rng<R: Rng>(dim: D, rng: &mut R) -> ArrayBase<Vec<A>, D>
+    pub fn randn_rng<R: Rng>(dim: D, rng: &mut R) -> ArrayBase<S, D>
     {
         let size = dim.size_checked().expect("Shape too large: overflow in size");
         let normal = Normal::new(1.0, 0.0);
         let iter = (0..size).map(|_| normal.ind_sample(rng).as_());
-        let arr = OwnedArray::from_iter(iter);
+        let arr = ArrayBase::from_iter(iter);
         arr.into_shape(dim).unwrap()
     }
 
-    pub fn randn(dim: D) -> ArrayBase<Vec<A>, D>
+    pub fn randn(dim: D) -> ArrayBase<S, D>
     {
         // Use the thread_rng once to seed a fast, non-crypto grade rng.
         // To use a crypto quality RNG, use randn_rng directly.
         let mut rng = rand::weak_rng();
-        ArrayBase::<Vec<A>, D>::randn_rng(dim, &mut rng)
+        ArrayBase::<S, D>::randn_rng(dim, &mut rng)
     }
 }