Installation

Toucan is a C++17 header-only library with a command-line executable. The build installs the public headers, CMake package files, and Toucan executable.

Requirements

• CMake 3.16 or newer
• A C++17 compiler
• Kokkos
• MPI with C++ support
• OpenMP
• Stork
• Condor, optional and required only for in-memory thermal solves
• nlohmann/json

Kokkos determines Toucan’s default host and device execution spaces. Configure Kokkos for the CPU or accelerator backend that the coupled application will use. Kokkos, MPI, OpenMP, Stork, and nlohmann/json are always required. Condor is required only when TOUCAN_ENABLE_CONDOR is enabled.

Configure and build

From the repository root:

cmake -S . -B build \
  -DCMAKE_BUILD_TYPE=Release \
  -DCMAKE_INSTALL_PREFIX="$PWD/install" \
  -DCMAKE_PREFIX_PATH="/path/to/kokkos;/path/to/stork;/path/to/condor;/path/to/json" \
  -DTOUCAN_ENABLE_CONDOR=ON
cmake --build build --parallel
cmake --install build

Add MPI’s package prefix to CMAKE_PREFIX_PATH when CMake cannot find it through the compiler wrapper or the system package configuration. Accelerator builds also require the appropriate Kokkos compiler wrapper and architecture flags.

Build without Condor

Condor support is enabled by default. Disable it for a file-input-only build:

cmake -S . -B build \
  -DCMAKE_BUILD_TYPE=Release \
  -DCMAKE_INSTALL_PREFIX="$PWD/install" \
  -DCMAKE_PREFIX_PATH="/path/to/kokkos;/path/to/stork;/path/to/json" \
  -DTOUCAN_ENABLE_CONDOR=OFF
cmake --build build --parallel
cmake --install build

With TOUCAN_ENABLE_CONDOR=ON, configuration fails if CMake cannot find Condor. With it set to OFF, Toucan does not search for or link Condor and the Thermal/File source remains available. Selecting Thermal/Condor in an input file passed to a Condor-disabled build reports that Toucan must be rebuilt with -DTOUCAN_ENABLE_CONDOR=ON.

The installed command is:

./install/bin/Toucan

With no settings argument, it prints Usage: Toucan <ToucanSettings.json>.

Use the repository helper

The included make.sh records one ORNL developer-machine configuration. It cleans build/, uses dependency locations under the invoking user’s home directory, applies AMD CPU and CUDA architecture flags, and builds with 24 jobs. Review those paths, compiler flags, and architecture choices before using the helper on another system. The explicit CMake commands above are the portable starting point.

Consume the installed headers

The installed package is named ToucanCore and exports the target Toucan_Core:

cmake_minimum_required(VERSION 3.16)
project(toucan_driver LANGUAGES CXX)

set(CMAKE_CXX_STANDARD 17)
set(CMAKE_CXX_STANDARD_REQUIRED ON)

find_package(ToucanCore CONFIG REQUIRED)

add_executable(toucan_driver main.cpp)
target_link_libraries(toucan_driver PRIVATE Toucan_Core)

Configure the consumer with Toucan and its dependencies on CMAKE_PREFIX_PATH. ToucanCoreConfig.cmake requests Kokkos, MPI, OpenMP, Stork, and nlohmann/json before loading the exported target. It requests Condor only when that Toucan installation was built with Condor support. The package sets ToucanCore_WITH_CONDOR to ON or OFF, and the exported target propagates the corresponding TOUCAN_ENABLE_CONDOR=1 or TOUCAN_ENABLE_CONDOR=0 compile definition to consumers.