python

Author: loriab

CMakeLists.txt

@@ -98,10 +98,14 @@ message(STATUS "Building using CMake ${CMAKE_VERSION} Generator ${CMAKE_GENERATO
 ### compiler-only
 
 ### library-only
+option_with_default(LIBINT2_ENABLE_PYTHON
+  "Build Python bindings (requires Python and Pybind11 and Eigen3)" OFF)
+option_with_default(LIBINT2_PREFIX_PYTHON_INSTALL
+  "For LIBINT2_ENABLE_PYTHON=ON, whether to install the Python module in the Linux manner to CMAKE_INSTALL_PREFIX or to not install it. See target libint2-python-wheel for alternate installation in the Python manner to Python_EXECUTABLE's site-packages." OFF)
+
 option_with_print(LIBINT2_ENABLE_MPFR
   "Use GNU MPFR library for high-precision testing (EXPERTS ONLY). Consumed at library build-time." OFF)
-option_with_print(LIBINT2_LOCAL_Eigen3_INSTALL
-  "Install an exported target with hard-coded Eigen3 dependency paths. This is potentially useful and important when consuming the compiled C++11 interface library so that the Libint library build and Libint consumer build use the same Eigen3 installation & ABI. This is at most a convenience when consuming the header-only C++11 interface library. See `LIBINT2_LOCAL_Eigen3_FIND`. Consumed at library build-time." OFF)
+## next one defined by `include(CTest)`
 
 #  <<<  Which Integrals Classes, Which Derivative Levels  >>>
 
@@ -275,7 +279,7 @@ endif()
 
 check_include_file_cxx(stdint.h HAVE_STDINT_H)  # limits.h?
 
-if(cxx_std_11 IN_LIST CMAKE_CXX_COMPILE_FEATURES)
+if (cxx_std_11 IN_LIST CMAKE_CXX_COMPILE_FEATURES)
     set(LIBINT_HAS_CXX11 1)
 endif()
 
@@ -296,7 +300,7 @@ booleanize01(LIBINT_PROFILE)
 
 # See notes at https://github.com/evaleev/libint/blob/master/INSTALL.md#prerequisites
 
-if(LIBINT2_ENABLE_MPFR)
+if (LIBINT2_ENABLE_MPFR)
     # mpfr detected at appropriate time for library (CMakeLists.txt.export), but prechecking here
     find_package(Multiprecision MODULE REQUIRED COMPONENTS gmpxx mpfr)
     set(LIBINT_HAS_MPFR 1)

INSTALL.md

@@ -238,13 +238,16 @@ Note that options, docs, and CMake components are focused on the C++ interface,
 
 * `LIBINT2_ENABLE_MPFR` — L — Use MPFR library to test Libint integrals in high precision (requires MPFR; experts only). [Default=OFF]
 * `LIBINT2_LOCAL_Eigen3_INSTALL` — L — Install an exported target with hard-coded Eigen3 dependency paths. This is potentially useful and important when consuming the compiled C++11 interface library so that the Libint library build and Libint consumer build use the same Eigen3 installation & ABI. This is at most a convenience when consuming the header-only C++11 interface library. See `LIBINT2_LOCAL_Eigen3_FIND`. [Default=OFF]
+* `LIBINT2_ENABLE_PYTHON` — L — Build Python bindings (requires Python and Eigen3; Boost and pybind11 recommended; [see prereq line](#prerequisites)). Can instead be enabled and built through separate CMake configuration after library build. [Default=OFF]
 
 
 ### Build Library How (G L) (TARBALL)
 
 
 ### Detecting Dependencies (G L C) (TARBALL)
 
+* `Python_EXECUTABLE` — L — Path to Python interpreter.
+* `CMAKE_PREFIX_PATH` — G L — Set to list of root directories to look for external dependencies. [Standard CMake variable](https://cmake.org/cmake/help/latest/variable/CMAKE_PREFIX_PATH.html)
 * `BOOST_ROOT` — G L C — Prefix to installation location (`BOOST_ROOT/include/boost/` exists)
 * `Boost_DIR` - G L C - Path to installation location of Boost's config file (`Boost_DIR/BoostConfig.cmake` exists)
 * `CMAKE_DISABLE_FIND_PACKAGE_Boost` — L — When Boost required for C++11 Libint API, disable its detection, thereby forcing use of bundled Boost. Note that this (and other Boost-hinting variables) can affect what is installed [see here](#packagers). [Standard CMake variable](https://cmake.org/cmake/help/latest/variable/CMAKE_DISABLE_FIND_PACKAGE_PackageName.html). [Default=OFF]
@@ -288,6 +291,7 @@ Note that options, docs, and CMake components are focused on the C++ interface,
 
 ### Install Paths (L) (TARBALL)
 
+* `LIBINT2_PREFIX_PYTHON_INSTALL` — L — For `LIBINT2_ENABLE_PYTHON=ON`, whether to install the Python module in the Linux manner to `CMAKE_INSTALL_PREFIX` or to not install it. Note: not a path; the installation sub-path below `CMAKE_INSTALL_PREFIX` is determined by querying `Python_EXECUTABLE`. For alternate installation in the Python manner to `Python_EXECUTABLE`'s site-packages, see target libint2-python-wheel. [Default=OFF]
 
 
 ### Miscellaneous (G L)
@@ -382,6 +386,7 @@ Note that options, docs, and CMake components are focused on the C++ interface,
 
 * `ENV(CPPFLAGS)=-I/path/to/boost/includes` --> `-D BOOST_ROOT=/path/to/boost/prefix`
 
+* `-D LIBINT2_PYTHON=ON` --> `-D LIBINT2_ENABLE_PYTHON=ON`
 * `-D LIBINT_USE_BUNDLED_BOOST=ON` --> `-D CMAKE_DISABLE_FIND_PACKAGE_Boost=ON` (standard CMake variable)
 * `--with-boost` & `--with-boost-libdir` --> see `BOOST_ROOT` & `Boost_DIR`
 * `-D LIBINT_LOCAL_Eigen3_INSTALL` --> `-D LIBINT2_LOCAL_Eigen3_INSTALL`

src/lib/libint/CMakeLists.txt

@@ -50,26 +50,28 @@ add_custom_target(libint-library-export DEPENDS "${EXPORT_STAGE_DIR}.tgz")
         -DLIBINT2_ALIGN_SIZE=${LIBINT_ALIGN_SIZE}
         -DLIBINT2_REALTYPE=${LIBINT2_REALTYPE}
         -DLIBINT2_ENABLE_MPFR=${LIBINT2_ENABLE_MPFR}
+        -DLIBINT2_ENABLE_PYTHON=${LIBINT2_ENABLE_PYTHON}
+        -DLIBINT2_PREFIX_PYTHON_INSTALL=${LIBINT2_PREFIX_PYTHON_INSTALL}
       )
-    if(Multiprecision_ROOT)
+    if (Multiprecision_ROOT)
         list(APPEND library_CMAKE_ARGS "-DMultiprecision_ROOT=${Multiprecision_ROOT}")
     endif()
-    if(Boost_DIR)
+    if (Boost_DIR)
         list(APPEND library_CMAKE_ARGS "-DBoost_DIR=${Boost_DIR}")
     endif()
-    if(BOOST_ROOT)
+    if (BOOST_ROOT)
         list(APPEND library_CMAKE_ARGS "-DBOOST_ROOT=${BOOST_ROOT}")
     endif()
-    if(CMAKE_DISABLE_FIND_PACKAGE_Boost)
+    if (CMAKE_DISABLE_FIND_PACKAGE_Boost)
         list(APPEND library_CMAKE_ARGS "-DCMAKE_DISABLE_FIND_PACKAGE_Boost=${CMAKE_DISABLE_FIND_PACKAGE_Boost}")
     endif()
-    if(Eigen3_DIR)
+    if (Eigen3_DIR)
         list(APPEND library_CMAKE_ARGS "-DEigen3_DIR=${Eigen3_DIR}")
     endif()
-    if(Eigen3_ROOT)
+    if (Eigen3_ROOT)
         list(APPEND library_CMAKE_ARGS "-DEigen3_ROOT=${Eigen3_ROOT}")
     endif()
-    if(LIBINT2_LOCAL_Eigen3_INSTALL)
+    if (LIBINT2_LOCAL_Eigen3_INSTALL)
         list(APPEND library_CMAKE_ARGS "-DLIBINT2_LOCAL_Eigen3_INSTALL=${LIBINT2_LOCAL_Eigen3_INSTALL}")
     endif()
 

src/lib/libint/CMakeLists.txt.export

@@ -36,6 +36,10 @@ include(CheckFunctionExists)
 
 option_with_print(LIBINT2_ENABLE_MPFR
   "Use GNU MPFR library for high-precision testing (requires MPFR. EXPERTS ONLY)" OFF)
+option_with_print(LIBINT2_ENABLE_PYTHON
+  "Build Python bindings (requires Python and Pybind11 and Eigen3)" OFF)
+option_with_print(LIBINT2_PREFIX_PYTHON_INSTALL
+  "For LIBINT2_ENABLE_PYTHON=ON, whether to install the Python module in the Linux manner to CMAKE_INSTALL_PREFIX or to not install it. See target libint2-python-wheel for alternate installation in the Python manner to Python_EXECUTABLE's site-packages." OFF)
 option_with_print(LIBINT2_LOCAL_Eigen3_INSTALL
   "Install an exported target with hard-coded Eigen3 dependency paths. This is potentially useful and important when consuming the compiled C++11 interface library so that the Libint library build and Libint consumer build use the same Eigen3 installation & ABI. This is at most a convenience when consuming the header-only C++11 interface library. In consumer build, set `LIBINT2_LOCAL_Eigen3_FIND=ON` before `find_package(Libint2) to load the exported Eigen3." OFF)
 option_with_print(CMAKE_DISABLE_FIND_PACKAGE_Boost
@@ -119,6 +123,17 @@ if (NOT LIBINT_HAS_EIGEN)  # TODO tmp wrong logic
     message(FATAL_ERROR "C++ API cannot be built without Eigen3; configure (via CMake) and install Eigen3 and add the install prefix to CMAKE_PREFIX_PATH, or add -DLIBINT2_REQUIRE_CXX_API=OFF to the CMake command line if the C++ API is not required")
 endif()
 
+# Python is optionally used for testing.
+# * But for Fortran, it's additionally required for preprocessing.
+# * And for Python bindings, it's required along with its headers.
+if (LIBINT2_ENABLE_PYTHON)
+    find_package(Python COMPONENTS Interpreter Development REQUIRED)
+elseif (LIBINT2_ENABLE_FORTRAN)
+    find_package(Python COMPONENTS Interpreter REQUIRED)
+else()
+    find_package(Python COMPONENTS Interpreter)
+endif()
+
 
 ################################# Main Project #################################
 include(CMakePackageConfigHelpers)