Adding New Dependencies

SparseBase contains two different types of dependencies:

Required dependencies.
Optional dependencies.

Required Dependencies

A dependency is required if the library loses a substantial amount of functionality without it. To keep the library simple and cross-platform, we currently avoid all required non-header-only dependencies.

Currently, for choosing required dependencies we suggest the following options in order of preference:

Look for header-only libraries
Check if it can be achieved by calling a Python script (we already depend on Python in our build system)
Look for UNIX commandline tools
Open a Github issue for discussion

Note

SparseBase is designed as an HPC library, so you shouldn’t be forced to use a header-only solution if it lacks the performance necessary. If this is the case please open an issue on Github so that we can discuss.

Header Only Dependencies

All header-only dependencies must be located in their own directory located at src/sparsebase/external This directory should contain the header files to be included as well as a LICENSE file containing the license for the dependency.

When choosing a header-only dependency please make sure it uses a permissive license (like MIT,Apache,BSD). Copy-left licences (like GPL) can cause legal issues since the SparseBase itself uses a permissive license. If you are not sure, please open an issue on Github.

Calling Python and UNIX Tools

This can be achieved easily by using std::system

Optional Dependencies

Optional dependencies in the context of SparseBase are libraries that for one reason or another can not be directly bundled with SparseBase. Some examples:

METIS (Has some compilation options that are best chosen by the user)
PATOH (Not open-source)

Note

If the dependency is header-only we suggest treating it as a required dependency even if it doesn’t have substantial effect on the library.

Optional dependencies must be build separately by users.

Here are the steps to add an optional dependency:

In the src/CMakeLists.txt file add a new option in the form USE_<dependency>. This will be set by the user to turn the dependency ON or OFF. It should always default to OFF.
```
option(USE_METIS "Enable METIS integration" OFF)
```
In the same file call the add_opt_library macro with the name of the library if it is ON. This name should match the library’s built file (ie, lib<name>.so or lib<name>.a etc.)
```
if(USE_METIS)
    add_opt_library("metis")
endif()
```
In the src/config.h.in file add #cmakedefine USE_<dependency>
```
#cmakedefine USE_METIS
```

Now the dependency should be accessible. The included files will be in sparsebase/external/<dependency>. You should surround every usage with #ifdef USE_<dependency> ... #endif.

#ifdef USE_METIS

#include "sparsebase/external/metis/metis.h"

template <typename IDType, typename NNZType, typename ValueType>
MetisPartition<IDType, NNZType, ValueType>::MetisPartition(){...}

#endif