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diff --git a/internal/ceres/schur_ordering.cc b/internal/ceres/schur_ordering.cc
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+// Ceres Solver - A fast non-linear least squares minimizer
+// Copyright 2010, 2011, 2012 Google Inc. All rights reserved.
+// http://code.google.com/p/ceres-solver/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// * Redistributions of source code must retain the above copyright notice,
+//   this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above copyright notice,
+//   this list of conditions and the following disclaimer in the documentation
+//   and/or other materials provided with the distribution.
+// * Neither the name of Google Inc. nor the names of its contributors may be
+//   used to endorse or promote products derived from this software without
+//   specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+// POSSIBILITY OF SUCH DAMAGE.
+//
+// Author: sameeragarwal@google.com (Sameer Agarwal)
+
+#include "ceres/schur_ordering.h"
+
+#include "ceres/graph.h"
+#include "ceres/graph_algorithms.h"
+#include "ceres/internal/scoped_ptr.h"
+#include "ceres/map_util.h"
+#include "ceres/parameter_block.h"
+#include "ceres/program.h"
+#include "ceres/residual_block.h"
+#include "glog/logging.h"
+
+namespace ceres {
+namespace internal {
+
+int ComputeSchurOrdering(const Program& program,
+                         vector<ParameterBlock*>* ordering) {
+  CHECK_NOTNULL(ordering)->clear();
+
+  scoped_ptr<Graph< ParameterBlock*> > graph(
+      CHECK_NOTNULL(CreateHessianGraph(program)));
+  int independent_set_size = IndependentSetOrdering(*graph, ordering);
+  const vector<ParameterBlock*>& parameter_blocks = program.parameter_blocks();
+
+  // Add the excluded blocks to back of the ordering vector.
+  for (int i = 0; i < parameter_blocks.size(); ++i) {
+    ParameterBlock* parameter_block = parameter_blocks[i];
+    if (parameter_block->IsConstant()) {
+      ordering->push_back(parameter_block);
+    }
+  }
+
+  return independent_set_size;
+}
+
+Graph<ParameterBlock*>*
+CreateHessianGraph(const Program& program) {
+  Graph<ParameterBlock*>* graph = new Graph<ParameterBlock*>;
+  const vector<ParameterBlock*>& parameter_blocks = program.parameter_blocks();
+  for (int i = 0; i < parameter_blocks.size(); ++i) {
+    ParameterBlock* parameter_block = parameter_blocks[i];
+    if (!parameter_block->IsConstant()) {
+      graph->AddVertex(parameter_block);
+    }
+  }
+
+  const vector<ResidualBlock*>& residual_blocks = program.residual_blocks();
+  for (int i = 0; i < residual_blocks.size(); ++i) {
+    const ResidualBlock* residual_block = residual_blocks[i];
+    const int num_parameter_blocks = residual_block->NumParameterBlocks();
+    ParameterBlock* const* parameter_blocks =
+        residual_block->parameter_blocks();
+    for (int j = 0; j < num_parameter_blocks; ++j) {
+      if (parameter_blocks[j]->IsConstant()) {
+        continue;
+      }
+
+      for (int k = j + 1; k < num_parameter_blocks; ++k) {
+        if (parameter_blocks[k]->IsConstant()) {
+          continue;
+        }
+
+        graph->AddEdge(parameter_blocks[j], parameter_blocks[k]);
+      }
+    }
+  }
+
+  return graph;
+}
+
+}  // namespace internal
+}  // namespace ceres