Add FindLAPACKE.cmake and export proxTVconfig.cmake.

FindLAPACKE.cmake is used to handle lapacke installations with no export targets.

Also complete the generation of proxTVconfig.cmake

Add a dummy project to test usage of proxTV from external project.

Add C Interface to Readme

CMakeLists.txt

@@ -0,0 +1,48 @@
+cmake_minimum_required(VERSION 2.8.12)
+#To avoid OpenMP warning: https://gitlab.kitware.com/cmake/cmake/issues/17292
+if(POLICY CMP0054)
+      cmake_policy(SET CMP0054 NEW)
+endif()
+
+project(proxTV
+        DESCRIPTION "Toolbox for fast Total Variation proximity operators"
+        LANGUAGES C CXX
+        )
+
+# Set VERSION
+# Since cmake v3.0 we can just give an option to project(proxTV VERSION 3.2.1 LANGUAGES C CXX)
+set(proxTV_VERSION_MAJOR 3)
+set(proxTV_VERSION_MINOR 2)
+set(proxTV_VERSION_PATCH 1)
+# set(proxTV_VERSION_TWEAK 0)
+set(proxTV_VERSION "${proxTV_VERSION_MAJOR}.${proxTV_VERSION_MINOR}.${proxTV_VERSION_PATCH}")
+message(STATUS "proxTV version: ${proxTV_VERSION}")
+
+# External Dependencies: {{{
+# Use FindLAPACKE from local cmake folder
+# FindLAPACK, FindOpenMP are already included in cmake installation.
+# Threads is for pthreads flags.
+# Append local module directory to the find_package search:
+list(APPEND CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/cmake)
+
+find_package(LAPACKE REQUIRED)
+message(STATUS "Lapacke found?: ${LAPACKE_FOUND}")
+message(STATUS "Lapacke libraries: ${LAPACKE_LIBRARIES}")
+
+find_package(LAPACK REQUIRED)
+message(STATUS "Lapack found?: ${LAPACKE_FOUND}")
+message(STATUS "Lapack libraries: ${LAPACK_LIBRARIES}")
+
+find_package(Threads)
+
+find_package(OpenMP)
+message(STATUS "OpenMP found?: ${OpenMP_FOUND}")
+
+add_subdirectory(src)
+
+# Test
+option(ENABLE_TESTING "Compile tests" OFF)
+if(${ENABLE_TESTING})
+    enable_testing()
+    add_subdirectory(test)
+endif()

README.md

@@ -33,6 +33,33 @@ More technically, the library provides efficient solvers for the following Total
 | Anisotropic Total Variation on a 3-dimensional signal (video denoising) | ![alt tag](docs/img/TV3D.png) |
 | Generalized N-dimensional Anisotropic Total Variation (tensor denoising) | ![alt tag](docs/img/TVND.png), with X(di) every possible 1-dimensional slice of X following dimension di.|
 
+## C interface
+
+You can use the **c** library using **cmake**. If `libproxTV` is not provided by your package-manager, install it from source:
+
+    mkdir proxTV-dev ; cd proxTV-dev
+    git clone https://github.com/albarji/proxTV proxTV
+    mkdir build ; cd build
+    cmake ../proxTV
+    make -j12
+    make install
+
+The required dependencies are `lapack` and `lapacke`, the c-interface for `lapack`, and optionally, but recommended: `OpenMP` with `pthreads` for multi-threading support.
+
+You can provide extra options to `cmake` via the command line or a gui (i.e `ccmake`).
+
+    cmake ../proxTV -DBUILD_SHARED_LIBS:BOOL=ON -DCMAKE_INSTALL_PREFIX=/opt/ -DENABLE_TESTING:BOOL=ON
+
+To use proxTV in your `cmake` project just write in your `CMakeLists.txt`:
+
+    find_package(proxTV)
+    add_executable(foo main.cpp)
+    target_link_libraries(foo PUBLIC proxTV::proxTV)
+
+That will propagate all the dependencies of proxTV to your target. If you haven't installed proxTV in a system folder, you have to point to the installation directory when configuring your project with `cmake`.
+
+    cmake /path/my_project_source_folder -DproxTV_DIR:PATH="/proxTV_install_folder/lib/cmake/proxTV"
+
 ## Python interface
 
 ### Quickstart

cmake/FindLAPACKE.cmake

@@ -0,0 +1,190 @@
+#.rst:
+# FindLAPACKE
+# -------------
+#
+# Find the LAPACKE library
+#
+# Using LAPACKE:
+#
+# ::
+#
+#   find_package(LAPACKE REQUIRED)
+#   include_directories(${LAPACKE_INCLUDE_DIRS})
+#   add_executable(foo foo.cc)
+#   target_link_libraries(foo ${LAPACKE_LIBRARIES})
+#
+# This module sets the following variables:
+#
+# ::
+#
+#   LAPACKE_FOUND - set to true if the library is found
+#   LAPACKE_INCLUDE_DIRS - list of required include directories
+#   LAPACKE_LIBRARIES - list of libraries to be linked
+#   LAPACKE_VERSION_MAJOR - major version number
+#   LAPACKE_VERSION_MINOR - minor version number
+#   LAPACKE_VERSION_PATCH - patch version number
+#   LAPACKE_VERSION_STRING - version number as a string (ex: "0.2.18")
+
+#=============================================================================
+# Copyright 2016 Hans J. Johnson <[email protected]>
+#
+# Distributed under the OSI-approved BSD License (the "License")
+#
+# This software is distributed WITHOUT ANY WARRANTY; without even the
+# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+#=============================================================================
+#
+set(LAPACKE_SEARCH_PATHS
+  ${LAPACKE_DIR}
+  $ENV{LAPACKE_DIR}
+  $ENV{CMAKE_PREFIX_PATH}
+  ${CMAKE_PREFIX_PATH}
+  /usr
+  /usr/local
+  /usr/local/opt/lapack  ## Mac Homebrew install path
+  /opt/LAPACKE
+)
+message(STATUS "LAPACKE_SEARCH_PATHS: ${LAPACKE_SEARCH_PATHS}")
+
+set(CMAKE_PREFIX_PATH ${LAPACKE_SEARCH_PATHS})
+list(REMOVE_DUPLICATES CMAKE_PREFIX_PATH)
+
+## First try to find LAPACKE with NO_MODULE,
+## As of 20160706 version 0.2.18 there is limited cmake support for LAPACKE
+## that is not as complete as this version, if found, use it
+## to identify the LAPACKE_VERSION_STRING and improve searching.
+find_package(LAPACKE NO_MODULE QUIET)
+if(LAPACKE_FOUND)
+  if(EXISTS ${LAPACKE_DIR}/lapacke-config-version.cmake)
+    include(${LAPACKE_DIR}/lapacke-config-version.cmake)
+    set(LAPACKE_VERSION_STRING ${PACKAGE_VERSION})
+    unset(PACKAGE_VERSION) # Use cmake conventional naming
+  endif()
+  find_package(LAPACK NO_MODULE QUIET) #Require matching versions here!
+  find_package(BLAS NO_MODULE QUIET)   #Require matching versions here!
+endif()
+
+##################################################################################################
+### First search for headers
+find_path(LAPACKE_CBLAS_INCLUDE_DIR 
+             NAMES cblas.h 
+             PATHS ${LAPACKE_SEARCH_PATHS} 
+             PATH_SUFFIXES include include/lapack)
+find_path(LAPACKE_LAPACKE_INCLUDE_DIR 
+             NAMES lapacke.h 
+             PATHS ${LAPACKE_SEARCH_PATHS} 
+             PATH_SUFFIXES include)
+
+##################################################################################################
+### Second, search for libraries
+set(PATH_SUFFIXES_LIST
+  lib64
+  lib
+)
+find_library(LAPACKE_LIB 
+                 NAMES lapacke
+                 PATHS ${LAPACKE_SEARCH_PATHS}
+                 PATH_SUFFIXES ${PATH_SUFFIXES_LIST})
+find_library(CBLAS_LIB 
+                 NAMES cblas
+                 PATHS ${LAPACKE_SEARCH_PATHS}
+                 PATH_SUFFIXES ${PATH_SUFFIXES_LIST})
+find_library(LAPACK_LIB 
+                 NAMES lapack
+                 PATHS ${LAPACKE_SEARCH_PATHS}
+                 PATH_SUFFIXES ${PATH_SUFFIXES_LIST})
+find_library(BLAS_LIB 
+                 NAMES blas
+                 PATHS ${LAPACKE_SEARCH_PATHS}
+                 PATH_SUFFIXES ${PATH_SUFFIXES_LIST})
+
+## TODO: Get version components
+# ------------------------------------------------------------------------
+#  Extract version information
+# ------------------------------------------------------------------------
+
+# WARNING: We may not be able to determine the version of some LAPACKE
+set(LAPACKE_VERSION_MAJOR 0)
+set(LAPACKE_VERSION_MINOR 0)
+set(LAPACKE_VERSION_PATCH 0)
+if(LAPACKE_VERSION_STRING)
+  string(REGEX REPLACE "([0-9]+).([0-9]+).([0-9]+)" "\\1" LAPACKE_VERSION_MAJOR "${LAPACKE_VERSION_STRING}")
+  string(REGEX REPLACE "([0-9]+).([0-9]+).([0-9]+)" "\\2" LAPACKE_VERSION_MINOR "${LAPACKE_VERSION_STRING}")
+  string(REGEX REPLACE "([0-9]+).([0-9]+).([0-9]+)" "\\3" LAPACKE_VERSION_PATCH "${LAPACKE_VERSION_STRING}")
+endif()
+
+#======================
+# Checks 'REQUIRED', 'QUIET' and versions.
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(LAPACKE FOUND_VAR LAPACKE_FOUND
+  REQUIRED_VARS LAPACKE_CBLAS_INCLUDE_DIR
+                LAPACKE_LAPACKE_INCLUDE_DIR
+                LAPACKE_LIB
+                LAPACK_LIB
+                CBLAS_LIB
+                BLAS_LIB
+  VERSION_VAR LAPACKE_VERSION_STRING
+)
+
+if (LAPACKE_FOUND)
+  set(LAPACKE_INCLUDE_DIRS ${LAPACKE_CBLAS_INCLUDE_DIR} ${LAPACKE_CBLAS_INCLUDE_DIR})
+  list(REMOVE_DUPLICATES LAPACKE_INCLUDE_DIRS)
+  if("${CMAKE_C_COMPILER_ID}" MATCHES ".*Clang.*" OR
+     "${CMAKE_C_COMPILER_ID}" MATCHES ".*GNU.*" OR
+     "${CMAKE_C_COMPILER_ID}" MATCHES ".*Intel.*"
+      ) #NOT MSVC
+    set(MATH_LIB m)
+  endif()
+  list(APPEND LAPACKE_LIBRARIES ${LAPACKE_LIB} ${LAPACK_LIB} ${BLAS_LIB} ${CBLAS_LIB})
+  # Check for a common combination, and find required gfortran support libraries
+
+  if(1)
+    if("${CMAKE_C_COMPILER_ID}" MATCHES ".*Clang.*" AND "${CMAKE_Fortran_COMPILER_ID}" MATCHES "GNU")
+          message(STATUS "\n\n WARNING: ${CMAKE_C_COMPILER} identified as ${CMAKE_C_COMPILER_ID}\n"
+                                   "AND: ${CMAKE_Fortran_COMPILER} identified as ${CMAKE_Fortran_COMPILER_ID}\n"
+                               "\n"
+                               "may be require special configurations.  The most common is the need to"
+                               "explicitly link C programs against the gfortran support library.")
+
+    endif()
+  else()
+    ## This code automated code is hard to determine if it is robust in many different environments.
+    # Check for a common combination, and find required gfortran support libraries
+    if("${CMAKE_C_COMPILER_ID}" MATCHES ".*Clang.*" AND "${CMAKE_Fortran_COMPILER_ID}" MATCHES "GNU")
+       include(FortranCInterface)
+       FortranCInterface_VERIFY() 
+       if(NOT FortranCInterface_VERIFIED_C)
+          message(FATAL_ERROR "C and fortran compilers are not compatible:\n${CMAKE_Fortran_COMPILER}:${CMAKE_C_COMPILER}")
+       endif()
+
+       execute_process(COMMAND ${CMAKE_Fortran_COMPILER} -print-file-name=libgfortran.a OUTPUT_VARIABLE FORTRANSUPPORTLIB ERROR_QUIET)
+       string(STRIP ${FORTRANSUPPORTLIB} FORTRANSUPPORTLIB)
+       if(EXISTS "${FORTRANSUPPORTLIB}")
+         list(APPEND LAPACKE_LIBRARIES ${FORTRANSUPPORTLIB})
+         message(STATUS "Appending fortran support lib: ${FORTRANSUPPORTLIB}")
+       else()
+         message(FATAL_ERROR "COULD NOT FIND libgfortran.a support library:${FORTRANSUPPORTLIB}:")
+       endif()
+    endif()
+  endif()
+  list(APPEND LAPACKE_LIBRARIES ${MATH_LIB})
+endif()
+
+mark_as_advanced(
+  LAPACKE_FOUND
+  LAPACKE_INCLUDE_DIRS
+  LAPACKE_LIBRARIES
+  LAPACKE_VERSION_MAJOR
+  LAPACKE_VERSION_MINOR
+  LAPACKE_VERSION_PATCH
+  LAPACKE_VERSION_STRING
+)
+
+## For debugging
+message(STATUS "LAPACKE_FOUND                  :${LAPACKE_FOUND}:  - set to true if the library is found")
+message(STATUS "LAPACKE_INCLUDE_DIRS           :${LAPACKE_INCLUDE_DIRS}: - list of required include directories")
+message(STATUS "LAPACKE_LIBRARIES              :${LAPACKE_LIBRARIES}: - list of libraries to be linked")
+message(STATUS "LAPACKE_VERSION_MAJOR          :${LAPACKE_VERSION_MAJOR}: - major version number")
+message(STATUS "LAPACKE_VERSION_MINOR          :${LAPACKE_VERSION_MINOR}: - minor version number")
+message(STATUS "LAPACKE_VERSION_PATCH          :${LAPACKE_VERSION_PATCH}: - patch version number")
+message(STATUS "LAPACKE_VERSION_STRING         :${LAPACKE_VERSION_STRING}: - version number as a string")

cmake/README.md

@@ -0,0 +1,7 @@
+Modern lapacke provides a lapacke-config.cmake (minimum version unconfirmed, but 3.7.1 does)
+so FindLAPACKE.cmake wouldn't be neccesary, (see #38)
+however this isn't reliable for older/other lapacke versions, so we provide a FindModule from: https://github.com/mrirecon/bart/blob/master/cmake/FindLAPACKE.cmake.
+
+Download with `curl -O https://raw.githubusercontent.com/mrirecon/bart/master/cmake/FindLAPACKE.cmake`
+
+This FindLapacke handles properly the case a lapacke-config.cmake exists in the system.

cmake/proxTVConfig.cmake

@@ -0,0 +1,6 @@
+include(CMakeFindDependencyMacro)
+find_dependency(LAPACKE)
+find_dependency(LAPACK)
+find_dependency(OpenMP)
+find_dependency(Threads)
+include("${CMAKE_CURRENT_LIST_DIR}/proxTVTargets.cmake")