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diff --git a/internal/ceres/tiny_solver_test.cc b/internal/ceres/tiny_solver_test.cc
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+
+// Ceres Solver - A fast non-linear least squares minimizer
+// Copyright 2017 Google Inc. All rights reserved.
+// http://ceres-solver.org/
+//
+// 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: mierle@gmail.com (Keir Mierle)
+
+#include "ceres/tiny_solver.h"
+#include "ceres/tiny_solver_test_util.h"
+
+#include <algorithm>
+#include <cmath>
+
+#include "gtest/gtest.h"
+
+namespace ceres {
+
+typedef Eigen::Matrix<double, 2, 1> Vec2;
+typedef Eigen::Matrix<double, 3, 1> Vec3;
+typedef Eigen::VectorXd VecX;
+
+class ExampleStatic {
+ public:
+  typedef double Scalar;
+  enum {
+    // Can also be Eigen::Dynamic.
+    NUM_RESIDUALS = 2,
+    NUM_PARAMETERS = 3,
+  };
+  bool operator()(const double* parameters,
+                  double* residuals,
+                  double* jacobian) const {
+    return EvaluateResidualsAndJacobians(parameters, residuals, jacobian);
+  }
+};
+
+class ExampleParametersDynamic {
+ public:
+  typedef double Scalar;
+  enum {
+    NUM_RESIDUALS = 2,
+    NUM_PARAMETERS = Eigen::Dynamic,
+  };
+
+  int NumParameters() const {
+    return 3;
+  }
+
+  bool operator()(const double* parameters,
+                  double* residuals,
+                  double* jacobian) const {
+    return EvaluateResidualsAndJacobians(parameters, residuals, jacobian);
+  }
+};
+
+class ExampleResidualsDynamic {
+ public:
+  typedef double Scalar;
+  enum {
+    NUM_RESIDUALS = Eigen::Dynamic,
+    NUM_PARAMETERS = 3,
+  };
+
+  int NumResiduals() const {
+    return 2;
+  }
+
+  bool operator()(const double* parameters,
+                  double* residuals,
+                  double* jacobian) const {
+    return EvaluateResidualsAndJacobians(parameters, residuals, jacobian);
+  }
+};
+
+class ExampleAllDynamic {
+ public:
+  typedef double Scalar;
+  enum {
+    NUM_RESIDUALS = Eigen::Dynamic,
+    NUM_PARAMETERS = Eigen::Dynamic,
+  };
+
+  int NumResiduals() const {
+    return 2;
+  }
+
+  int NumParameters() const {
+    return 3;
+  }
+
+  bool operator()(const double* parameters,
+                  double* residuals,
+                  double* jacobian) const {
+    return EvaluateResidualsAndJacobians(parameters, residuals, jacobian);
+  }
+};
+
+template<typename Function, typename Vector>
+void TestHelper(const Function& f, const Vector& x0) {
+  Vector x = x0;
+  Vec2 residuals;
+  f(x.data(), residuals.data(), NULL);
+  EXPECT_GT(residuals.squaredNorm() / 2.0, 1e-10);
+
+  TinySolver<Function> solver;
+  solver.Solve(f, &x);
+  EXPECT_NEAR(0.0, solver.summary.final_cost, 1e-10);
+}
+
+// A test case for when the cost function is statically sized.
+TEST(TinySolver, SimpleExample) {
+  Vec3 x0(0.76026643, -30.01799744, 0.55192142);
+  ExampleStatic f;
+
+  TestHelper(f, x0);
+}
+
+// A test case for when the number of parameters is dynamically sized.
+TEST(TinySolver, ParametersDynamic) {
+  VecX x0(3);
+  x0 << 0.76026643, -30.01799744, 0.55192142;
+
+  ExampleParametersDynamic f;
+
+  TestHelper(f, x0);
+}
+
+// A test case for when the number of residuals is dynamically sized.
+TEST(TinySolver, ResidualsDynamic) {
+  Vec3 x0(0.76026643, -30.01799744, 0.55192142);
+
+  ExampleResidualsDynamic f;
+
+  TestHelper(f, x0);
+}
+
+// A test case for when the number of parameters and residuals is
+// dynamically sized.
+TEST(TinySolver, ParametersAndResidualsDynamic) {
+  VecX x0(3);
+  x0 << 0.76026643, -30.01799744, 0.55192142;
+
+  ExampleAllDynamic f;
+
+  TestHelper(f, x0);
+}
+
+}  // namespace ceres