diff --git a/exercice_3/src/CMakeLists.txt b/exercice_3/src/CMakeLists.txt
index a2df682..07d7fb3 100644
--- a/exercice_3/src/CMakeLists.txt
+++ b/exercice_3/src/CMakeLists.txt
@@ -1,82 +1,85 @@
 cmake_minimum_required (VERSION 3.1)
 project (Particles)
 
 set(CMAKE_CXX_STANDARD 14)
 set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${PROJECT_SOURCE_DIR}/cmake")
 
 ################################################################
 # libpart
 ################################################################
 
 add_library(part
   compute_boundary.cc
   compute_verlet_integration.cc 
   particle.cc 
   planet.cc
   compute_gravity.cc 
   csv_reader.cc 
   particles_factory_interface.cc 
   planets_factory.cc 
   compute_contact.cc 
   compute_kinetic_energy.cc 
   csv_writer.cc 
   system.cc 
   compute_energy.cc 
   compute_potential_energy.cc 
   ping_pong_ball.cc
   material_point.cc 
   system_evolution.cc 
   ping_pong_balls_factory.cc 
   compute_interaction.cc
   compute_temperature.cc
   material_points_factory.cc 
   )
 
 ################################################################
 # FFTW
 ################################################################
 
 option(USE_FFTW "Use FFTW library" ON)
 
 if (USE_FFTW)
   set(FFTW_LIBRARY_PATH CACHE PATH "Where to search FFTW3")
   find_library(FFTW_LIBRARY fftw3 ${FFTW_LIBRARY_PATH})
   target_link_libraries(part fftw3)
 endif (USE_FFTW)
 
 add_executable(particles main.cc)
 target_link_libraries(particles part)
 
 
 ################################################################
 # Google test
 ################################################################
 
 include(GoogleTest)
 enable_testing()
 find_package(GTest)
 if (GTEST_FOUND)
 include_directories(${GTEST_INCLUDE_DIRS})
 add_executable(test_kepler test_kepler.cc)
 add_executable(test_fft test_fft.cc)
+add_executable(test_temperature test_temperature.cc)
 target_link_libraries(test_kepler part ${GTEST_BOTH_LIBRARIES} pthread)
 target_link_libraries(test_fft part ${GTEST_BOTH_LIBRARIES} ${FFTW_LIBRARY} pthread)
+target_link_libraries(test_temperature part ${GTEST_BOTH_LIBRARIES} ${FFTW_LIBRARY} pthread)
 gtest_discover_tests(test_kepler)
 gtest_discover_tests(test_fft)
+gtest_discover_tests(test_temperature)
 endif()
 
 ################################################################
 # Doxygen
 ################################################################
 
 find_package(Doxygen)
 if (DOXYGEN_FOUND)
 
 # to set other options, read: https://cmake.org/cmake/help/v3.9/module/FindDoxygen.html
 doxygen_add_docs(
     doxygen
     ${PROJECT_SOURCE_DIR}
     COMMENT "Generate html pages"
 )
 add_custom_target(doc DEPENDS doxygen)
 endif(DOXYGEN_FOUND)
diff --git a/exercice_3/src/test_temperature.cc b/exercice_3/src/test_temperature.cc
new file mode 100644
index 0000000..7e8bb22
--- /dev/null
+++ b/exercice_3/src/test_temperature.cc
@@ -0,0 +1,41 @@
+#include "compute_temperature.hh"
+#include "material_points_factory.hh"
+#include "my_types.hh"
+#include "system_evolution.hh"
+#include <gtest/gtest.h>
+
+/*****************************************************************/
+TEST(COMPUTE_TEMPERATURE, homogeneous) {
+  UInt N = 512;
+
+  System system = System();
+
+  for (int i = 0; i < N; i++) {
+    for (int j = 0; j < N; j++) {
+      // auto &val = std::get<2>(entry);
+      std::stringstream sstr;
+      // position (i, j, 0);  temperature 10; 0 for the rest
+      std::string line =
+          std::to_string(i) + " " + std::to_string(i) + " 0 0 0 0 0 0 0 0 10 0";
+      sstr << line;
+      auto p = MaterialPointsFactory::getInstance().createParticle();
+      sstr >> *p;
+      system.addParticle(std::move(p));
+    }
+  }
+
+  ComputeTemperature compute_temperature = ComputeTemperature();
+  // test 5 iterations - nothing should change regardless of the number of
+  // iterations
+  int nsteps = 5;
+  for (int step = 0; step < nsteps; ++step)
+    compute_temperature.compute(system);
+
+  UInt nb_particles = system.getNbParticles();
+
+  for (UInt p = 0; p < nb_particles; ++p) {
+    MaterialPoint *mpoint =
+        static_cast<MaterialPoint *>(&system.getParticle(p));
+    ASSERT_NEAR(mpoint->getTemperature(), 10, 1e-10);
+  }
+}