From 5d2790aa5e964c970c74e92c6a9a97f4a5fc5d97 Mon Sep 17 00:00:00 2001
From: Alex Cunningham <alexgcunningham@gmail.com>
Date: Fri, 18 Nov 2011 19:38:55 +0000
Subject: [PATCH] Added fixme comments in LDL

---
 gtsam/base/cholesky.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/gtsam/base/cholesky.cpp b/gtsam/base/cholesky.cpp
index a437c9e13..16f07f5ab 100644
--- a/gtsam/base/cholesky.cpp
+++ b/gtsam/base/cholesky.cpp
@@ -179,14 +179,14 @@ Eigen::LDLT<Matrix>::TranspositionType ldlPartial(Matrix& ABC, size_t nFrontal)
       throw NegativeMatrixException();
   }
 
-  Vector sqrtD = ldlt.vectorD().cwiseSqrt();
+  Vector sqrtD = ldlt.vectorD().cwiseSqrt(); // FIXME: we shouldn't do sqrt in LDL
   if (debug) cout << "Dsqrt: " << sqrtD << endl;
 
   // U = sqrtD * L^
   Matrix U = ldlt.matrixU();
 
   // we store the permuted upper triangular matrix
-  ABC.block(0,0,nFrontal,nFrontal)  = sqrtD.asDiagonal() * U;
+  ABC.block(0,0,nFrontal,nFrontal)  = sqrtD.asDiagonal() * U; // FIXME: this isn't actually LDL', it's Cholesky
   if(debug) cout << "R:\n" << ABC.topLeftCorner(nFrontal,nFrontal) << endl;
   //  toc(1, "ldl");