From bf504d30db3315027b2dd6f13eb52a1c1a1db651 Mon Sep 17 00:00:00 2001
From: Frank Dellaert <dellaert@gmail.com>
Date: Fri, 18 Dec 2009 06:11:19 +0000
Subject: [PATCH] new concatVectors call

---
 cpp/Vector.cpp     | 41 +++++++++++++++++++++++------------------
 cpp/Vector.h       |  7 ++++++-
 cpp/testVector.cpp | 11 ++++++++---
 3 files changed, 37 insertions(+), 22 deletions(-)

diff --git a/cpp/Vector.cpp b/cpp/Vector.cpp
index 79a7bf383..c98a5aa0a 100644
--- a/cpp/Vector.cpp
+++ b/cpp/Vector.cpp
@@ -238,31 +238,36 @@ namespace gtsam {
 	  return make_pair(pseudo/precision, precision);
   }
 
+  /* ************************************************************************* */
+  Vector concatVectors(const std::list<Vector>& vs)
+  {
+    int dim = 0;
+    BOOST_FOREACH(Vector v, vs)
+      dim += v.size();
+
+    Vector A(dim);
+    int index = 0;
+    BOOST_FOREACH(Vector v, vs) {
+      for(size_t d = 0; d < v.size(); d++)
+        A(d+index) = v(d);
+      index += v.size();
+    }
+
+    return A;
+  }
+
   /* ************************************************************************* */
   Vector concatVectors(size_t nrVectors, ...)
   {
-    int dimA = 0;
     va_list ap;
+    list<Vector> vs;
     va_start(ap, nrVectors);
-    Vector* V;
-    for( size_t i = 0 ; i < nrVectors ; i++)
-    {
-      V = va_arg(ap, Vector*);
-      dimA += V->size();
+    for( size_t i = 0 ; i < nrVectors ; i++) {
+    	Vector* V = va_arg(ap, Vector*);
+      vs.push_back(*V);
     }
     va_end(ap);
-    va_start(ap, nrVectors);
-    Vector A(dimA);
-    int index = 0;
-    for( size_t i = 0 ; i < nrVectors ; i++)
-    {
-      V = va_arg(ap, Vector *);
-      for(size_t d = 0; d < V->size(); d++)
-        A(d+index) = (*V)(d);
-      index += V->size();
-    }  
-    
-    return A;
+    return concatVectors(vs);
   }
   
   /* ************************************************************************* */
diff --git a/cpp/Vector.h b/cpp/Vector.h
index 29899942c..fa93d1ae0 100644
--- a/cpp/Vector.h
+++ b/cpp/Vector.h
@@ -9,6 +9,7 @@
 
 #pragma once
 
+#include <list>
 #include <boost/numeric/ublas/vector.hpp>
 #include <boost/random/linear_congruential.hpp>
 
@@ -167,8 +168,12 @@ std::pair<Vector, double> weightedPseudoinverse(const Vector& v, const Vector& s
 /**
  * concatenate Vectors
  */
-Vector concatVectors(size_t nrVectors, ...);
+Vector concatVectors(const std::list<Vector>& vs);
 
+/**
+ * concatenate Vectors
+ */
+Vector concatVectors(size_t nrVectors, ...);
 
 /**
  * random vector
diff --git a/cpp/testVector.cpp b/cpp/testVector.cpp
index 7035d0f20..fb19c2966 100644
--- a/cpp/testVector.cpp
+++ b/cpp/testVector.cpp
@@ -120,10 +120,15 @@ TEST( TestVector, concatVectors)
   Vector C(7);
   for(int i = 0; i < 2; i++) C(i) = A(i);
   for(int i = 0; i < 5; i++) C(i+2) = B(i);
-	
-  Vector AB = concatVectors(2, &A, &B);
 
-  CHECK(AB == C);
+  list<Vector> vs;
+  vs.push_back(A);
+  vs.push_back(B);
+  Vector AB1 = concatVectors(vs);
+  CHECK(AB1 == C);
+
+  Vector AB2 = concatVectors(2, &A, &B);
+  CHECK(AB2 == C);
 }
 
 /* ************************************************************************* */