Merge from trunk

git-svn-id: svn+ssh://scm.gforge.inria.fr/svnroot/gudhi/branches/subsampling_and_spatialsearching@1451 636b058d-ea47-450e-bf9e-a15bfbe3eedb

Former-commit-id: fd62937e290abdaf84b406897855e15267b9ebd4

7 files changed, 34 insertions, 51 deletions

diff --git a/data/points/generator/CMakeLists.txt b/data/points/generator/CMakeLists.txt
index e29eb19c..f559610c 100644
--- a/data/points/generator/CMakeLists.txt
+++ b/data/points/generator/CMakeLists.txt
@@ -13,8 +13,6 @@ if(CGAL_FOUND)
       # on cube is not available in CGAL
       add_test(hypergenerator_in_cube_7000_12_10.8 ${CMAKE_CURRENT_BINARY_DIR}/hypergenerator in cube inCube.off 7000 12 10.8)
       add_test(hypergenerator_in_cube_50000_2 ${CMAKE_CURRENT_BINARY_DIR}/hypergenerator in cube inCube.off 50000 3)
-      endif()
-  else()
-    message(WARNING "CGAL version: ${CGAL_VERSION} is too old to compile hypergenerator. Version 4.6.0 is required.")
-  endif ()
-endif()
+      endif(EIGEN3_FOUND)
+  endif(NOT CGAL_VERSION VERSION_LESS 4.6.0)
+endif(CGAL_FOUND)
diff --git a/src/Alpha_complex/example/CMakeLists.txt b/src/Alpha_complex/example/CMakeLists.txt
index f1c7ae97..71a95d61 100644
--- a/src/Alpha_complex/example/CMakeLists.txt
+++ b/src/Alpha_complex/example/CMakeLists.txt
@@ -28,10 +28,6 @@ if(CGAL_FOUND)
         add_test(alphaoffreader_doc_60_diff_files ${DIFF_PATH} ${CMAKE_CURRENT_BINARY_DIR}/alphaoffreader_result_60.txt ${CMAKE_CURRENT_BINARY_DIR}/alphaoffreader_for_doc_60.txt)
         add_test(alphaoffreader_doc_32_diff_files ${DIFF_PATH} ${CMAKE_CURRENT_BINARY_DIR}/alphaoffreader_result_32.txt ${CMAKE_CURRENT_BINARY_DIR}/alphaoffreader_for_doc_32.txt)
       endif()
-    else()
-      message(WARNING "Eigen3 not found. Version 3.1.0 is required for Alpha complex examples.")
-    endif()
-  else()
-    message(WARNING "CGAL version: ${CGAL_VERSION} is too old to compile Alpha complex examples. Version 4.7.0 is required.")
-  endif ()
-endif()
+    endif(EIGEN3_FOUND)
+  endif(NOT CGAL_VERSION VERSION_LESS 4.7.0)
+endif(CGAL_FOUND)
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index c05ce205..e9d24d2d 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -32,12 +32,14 @@ else()
   # A fix would be to use https://cmake.org/cmake/help/v3.1/prop_gbl/CMAKE_CXX_KNOWN_FEATURES.html 
   # or even better https://cmake.org/cmake/help/v3.1/variable/CMAKE_CXX_STANDARD.html
   # but it implies to use cmake version 3.1 at least.
-  find_package(CGAL)
+
+  # find CGAL in QUIET mode for cmake to be less verbose when CGAL is not found.
+  find_package(CGAL QUIET)
   # Only CGAL versions > 4.4 supports what Gudhi uses from CGAL
-  if (CGAL_VERSION VERSION_LESS 4.4.0)
+  if (CGAL_VERSION VERSION_LESS 4.4.0 AND CGAL_FOUND)
     message("CGAL version ${CGAL_VERSION} is considered too old to be used by Gudhi.")
     unset(CGAL_FOUND)
-  endif()
+  endif(CGAL_VERSION VERSION_LESS 4.4.0 AND CGAL_FOUND)
   if(CGAL_FOUND)
     message(STATUS "CGAL version: ${CGAL_VERSION}.")
     include( ${CGAL_USE_FILE} )
diff --git a/src/Persistent_cohomology/example/CMakeLists.txt b/src/Persistent_cohomology/example/CMakeLists.txt
index bae652c5..d6bc60be 100644
--- a/src/Persistent_cohomology/example/CMakeLists.txt
+++ b/src/Persistent_cohomology/example/CMakeLists.txt
@@ -48,8 +48,6 @@ if(GMP_FOUND)
 
    add_test(rips_multifield_persistence_2_71 ${CMAKE_CURRENT_BINARY_DIR}/rips_multifield_persistence ${CMAKE_SOURCE_DIR}/data/points/Kl.txt -r 0.2 -d 3 -p 2 -q 71 -m 100)
    endif(GMPXX_FOUND)
-else()
-  # message(WARNING "GMP not found.")
 endif(GMP_FOUND)
 
 if(CGAL_FOUND)
@@ -81,13 +79,6 @@ if(CGAL_FOUND)
       add_test(alpha_complex_persistence_2_0_45 ${CMAKE_CURRENT_BINARY_DIR}/alpha_complex_persistence ${CMAKE_SOURCE_DIR}/data/points/tore3D_300.off -m 0.45 -p 2)
       add_test(periodic_alpha_complex_3d_persistence_2_0 ${CMAKE_CURRENT_BINARY_DIR}/periodic_alpha_complex_3d_persistence ${CMAKE_SOURCE_DIR}/data/points/grid_10_10_10_in_0_1.off ${CMAKE_SOURCE_DIR}/data/points/iso_cuboid_3_in_0_1.txt 2 0)
       add_test(custom_persistence_sort ${CMAKE_CURRENT_BINARY_DIR}/custom_persistence_sort)
-
-    else()
-      message(WARNING "Eigen3 not found. Version 3.1.0 is required for Alpha complex persistence examples.")
     endif(EIGEN3_FOUND)
-  else()
-    message(WARNING "CGAL version: ${CGAL_VERSION} is too old to compile Alpha complex persistence examples. Version 4.7.0 is required.")
-  endif ()
-else()
-  # message(WARNING "CGAL not found.")
+  endif (NOT CGAL_VERSION VERSION_LESS 4.7.0)
 endif(CGAL_FOUND)
diff --git a/src/Witness_complex/example/CMakeLists.txt b/src/Witness_complex/example/CMakeLists.txt
index 48ba9279..4d67e0d0 100644
--- a/src/Witness_complex/example/CMakeLists.txt
+++ b/src/Witness_complex/example/CMakeLists.txt
@@ -11,10 +11,6 @@ if(CGAL_FOUND)
       add_executable ( witness_complex_sphere witness_complex_sphere.cpp )
       target_link_libraries(witness_complex_sphere ${Boost_SYSTEM_LIBRARY} ${CGAL_LIBRARY})
       add_test( witness_complex_sphere_10 ${CMAKE_CURRENT_BINARY_DIR}/witness_complex_sphere 10)   
-    else()
-      message(WARNING "Eigen3 not found. Version 3.1.0 is required for witness_complex_sphere example.")      
-    endif()
-  else()
-    message(WARNING "CGAL version: ${CGAL_VERSION} is too old to compile witness_complex_sphere example. Version 4.6.0 is required.")
-  endif ()
+    endif(EIGEN3_FOUND)
+  endif (NOT CGAL_VERSION VERSION_LESS 4.6.0)
 endif()
diff --git a/src/common/doc/main_page.h b/src/common/doc/main_page.h
index 2391e147..9146bed1 100644
--- a/src/common/doc/main_page.h
+++ b/src/common/doc/main_page.h
@@ -154,6 +154,7 @@
 */
 
 /*! \page installation Gudhi installation
+ *  \tableofcontents
  * As Gudhi is a header only library, there is no need to install the library.
  * 
  * Examples of Gudhi headers inclusion can be found in \ref demos.
@@ -162,6 +163,20 @@
  * The library uses c++11 and requires <a target="_blank" href="http://www.boost.org/">Boost</a> with version 1.48.0 or
  * more recent. It is a multi-platform library and compiles on Linux, Mac OSX and Visual Studio 2015.
  * 
+ * \subsection demos Demos and examples
+ * To build the demos and examples, run the following commands in a terminal:
+\verbatim  cd /path-to-gudhi/
+mkdir build
+cd build/
+cmake ..
+make \endverbatim
+ * A list of examples is available <a href="examples.html">here</a>.
+ * 
+ * \subsection testsuites Test suites
+ * To test your build, run the following command in a terminal:
+ * \verbatim  make test \endverbatim
+ * 
+ * \section optionallibrary Optional third-party library
  * \subsection gmp GMP:
  * The multi-field persistent homology algorithm requires GMP which is a free library for arbitrary-precision
  * arithmetic, operating on signed integers, rational numbers, and floating point numbers.
@@ -176,7 +191,8 @@
  * Having GMP version 4.2 or higher installed is recommended.
  * 
  * \subsection cgal CGAL:
- * CGAL is a C++ library which provides easy access to efficient and reliable geometric algorithms.
+ * The \ref alpha_complex data structure and few examples requires CGAL, which is a C++ library which provides easy
+ * access to efficient and reliable geometric algorithms.
  * 
  * Having CGAL version 4.4 or higher installed is recommended. The procedure to install this library according to
  * your operating system is detailed here http://doc.cgal.org/latest/Manual/installation.html
@@ -205,6 +221,7 @@
  * Persistent_cohomology/custom_persistence_sort.cpp</a>
  * 
  * \subsection eigen3 Eigen3:
+ * The \ref alpha_complex data structure and few examples requires
  * <a target="_blank" href="http://eigen.tuxfamily.org/">Eigen3</a> is a C++ template library for linear algebra:
  * matrices, vectors, numerical solvers, and related algorithms.
  * 
@@ -270,19 +287,6 @@
  * \li <a href="_persistent_cohomology_2custom_persistence_sort_8cpp-example.html">
  * Persistent_cohomology/custom_persistence_sort.cpp</a>
  * 
- * \subsection demos Demos and examples
- * To build the demos and examples, run the following commands in a terminal:
-\verbatim  cd /path-to-gudhi/
-mkdir build
-cd build/
-cmake ..
-make \endverbatim
- * A list of examples is available <a href="examples.html">here</a>.
- * 
- * \subsection testsuites Test suites
- * To test your build, run the following command in a terminal:
- * \verbatim  make test \endverbatim
- * 
  * \section Contributions Bug reports and contributions
  * Please help us improving the quality of the GUDHI library. You may report bugs or suggestions to:
  * \verbatim  Contact: gudhi-users@lists.gforge.inria.fr \endverbatim
diff --git a/src/common/example/CMakeLists.txt b/src/common/example/CMakeLists.txt
index 4ea8c9cb..0da3dcc0 100644
--- a/src/common/example/CMakeLists.txt
+++ b/src/common/example/CMakeLists.txt
@@ -12,10 +12,6 @@ if(CGAL_FOUND)
       add_executable ( cgaloffreader CGAL_points_off_reader.cpp )
       target_link_libraries(cgaloffreader  ${Boost_SYSTEM_LIBRARY} ${CGAL_LIBRARY})
       add_test(cgaloffreader ${CMAKE_CURRENT_BINARY_DIR}/cgaloffreader ${CMAKE_SOURCE_DIR}/data/points/alphacomplexdoc.off)
-    else()
-      message(WARNING "Eigen3 not found. Version 3.1.0 is required for cgaloffreader example.")
-    endif()
-  else()
-    message(WARNING "CGAL version: ${CGAL_VERSION} is too old to compile cgaloffreader example. Version 4.7.0 is required.")
-  endif ()
+    endif(EIGEN3_FOUND)
+  endif (NOT CGAL_VERSION VERSION_LESS 4.7.0)
 endif()