From 8d28763339095fc84b6f79834266dbfd4b983b59 Mon Sep 17 00:00:00 2001
From: Richard Roberts <richard.jw.roberts@gmail.com>
Date: Tue, 12 Jan 2010 16:12:31 +0000
Subject: [PATCH] Vector and Matrix initialization optimization

---
 cpp/Matrix.cpp | 7 +++----
 cpp/Vector.cpp | 4 ++--
 2 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/cpp/Matrix.cpp b/cpp/Matrix.cpp
index 65bed6976..edbec380a 100644
--- a/cpp/Matrix.cpp
+++ b/cpp/Matrix.cpp
@@ -60,8 +60,7 @@ Matrix Matrix_(size_t m, size_t n, ...) {
 /* ************************************************************************* */
 Matrix zeros( size_t m, size_t n )
 {
-  Matrix A(m,n);
-  fill(A.data().begin(),A.data().end(),0.0);
+  Matrix A(m,n, 0.0);
   return A;
 }
 
@@ -313,7 +312,7 @@ weighted_eliminate(Matrix& A, Vector& b, const Vector& sigmas) {
 	// Then update A and b by substituting x with d-rS, zero-ing out x's column.
 	for (int j=0; j<n; ++j) {
 		// extract the first column of A
-		Vector a = column(A, j);
+		Vector a(column(A, j));
 		if (verbose) print(a,"a = ");
 
 		// Calculate weighted pseudo-inverse and corresponding precision
@@ -326,7 +325,7 @@ weighted_eliminate(Matrix& A, Vector& b, const Vector& sigmas) {
 		if (verbose) print(pseudo, "pseudo = ");
 
 		// create solution and copy into r
-		Vector r = basis(n, j);
+		Vector r(basis(n, j));
 		for (int j2=j+1; j2<n; ++j2)
 			r(j2) = inner_prod(pseudo, column(A, j2));
 		if (verbose) print(r, "r = ");
diff --git a/cpp/Vector.cpp b/cpp/Vector.cpp
index 8a89f90da..09518a6cd 100644
--- a/cpp/Vector.cpp
+++ b/cpp/Vector.cpp
@@ -80,7 +80,7 @@ namespace gtsam {
   
   /* ************************************************************************* */
   Vector repeat(size_t n, double value) {
-    Vector v(n); fill_n(v.begin(),n,value);
+    Vector v(n, value);
     return v;
   }
 
@@ -246,7 +246,7 @@ namespace gtsam {
 	  }
 	  // precision = a'inv(Sigma)a
 	  if (precision<1e-9) return make_pair(zero(m), precision);
-	  Vector pseudo = emul(precisions,a);
+	  Vector pseudo(emul(precisions,a));
 	  return make_pair(pseudo/precision, precision);
   }