Add Rand for nmat.

src/ndim/nmat.rs

@@ -1,4 +1,5 @@
 use core::num::{One, Zero};
+use core::rand::{Rand, Rng, RngUtil};
 use core::vec::{from_elem, swap, all, all2};
 use std::cmp::FuzzyEq;
 use traits::dim::Dim;
@@ -250,6 +251,23 @@ impl<D, T:FuzzyEq<T>> FuzzyEq<T> for NMat<D, T>
   { all2(self.mij, other.mij, |a, b| a.fuzzy_eq_eps(b, epsilon)) }
 }
 
+impl<D: Dim, T: Rand + Zero + Copy> Rand for NMat<D, T>
+{
+  fn rand<R: Rng>(rng: &R) -> NMat<D, T>
+  {
+    let     dim = Dim::dim::<D>();
+    let mut res : NMat<D, T> = Zero::zero();
+
+    for uint::range(0u, dim) |i|
+    {
+      for uint::range(0u, dim) |j|
+      { res.set(i, j, &rng.gen()); }
+    }
+
+    res
+  }
+}
+
 impl<D: Dim, T: ToStr> ToStr for NMat<D, T>
 {
   fn to_str(&self) -> ~str