From ce70480ae0366df4f927b1af17595bf575c9fa84 Mon Sep 17 00:00:00 2001
From: Alex Cunningham <alexgcunningham@gmail.com>
Date: Wed, 30 Mar 2011 14:09:34 +0000
Subject: [PATCH] Made keys_ protected to allow initialization in a constructor
 body, added constructor for NonlinearFactor allowing more than two keys

---
 gtsam/inference/Factor.h          | 3 ++-
 gtsam/nonlinear/NonlinearFactor.h | 8 ++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/gtsam/inference/Factor.h b/gtsam/inference/Factor.h
index e9ac657ea..2e8b42603 100644
--- a/gtsam/inference/Factor.h
+++ b/gtsam/inference/Factor.h
@@ -70,7 +70,8 @@ public:
   /** Const iterator over keys */
   typedef typename std::vector<Key>::const_iterator const_iterator;
 
-private:
+//private: // FIXME: factors that manually initialize keys_ break in this case
+protected:
 
   // The keys involved in this factor
   std::vector<Key> keys_;
diff --git a/gtsam/nonlinear/NonlinearFactor.h b/gtsam/nonlinear/NonlinearFactor.h
index ffd4a2585..5986882e0 100644
--- a/gtsam/nonlinear/NonlinearFactor.h
+++ b/gtsam/nonlinear/NonlinearFactor.h
@@ -99,6 +99,14 @@ namespace gtsam {
 			Factor<Symbol>(j1,j2), noiseModel_(noiseModel) {
 		}
 
+		/**
+		 * Constructor - arbitrary number of keys
+		 * @param keys is the set of Symbols in the factor
+		 */
+		NonlinearFactor(const SharedGaussian& noiseModel, const std::set<Symbol>& keys) :
+			Factor<Symbol>(keys), noiseModel_(noiseModel) {
+		}
+
 		/** print */
 		virtual void print(const std::string& s = "") const {
 			std::cout << s << ": NonlinearFactor\n";