Installation

Requirements

Fulqrum is a mix of C++ and Python, glued together by a Cython interface.

Python

Required

Package	Minimum version	Description
cython	3.0.5	The glue between C++ and Python
numpy	1.25	Used as array interface between Python and C++
orjson	any	IO for saving operators
psutil	any	Get system information such as available memory
scipy	1.11.1	Needed for scipy.sparse.linalg.LinearOperator class

Optional

Package	Minimum version	Description
qiskit	1.0	Conversion between Qiskit operators and Fulqrum types
openfermion	1.6.1	Conversion between OpenFermion operators and Fulqrum types
primme	3.2.3	Eigensolver for Hermitian systems

C++

Fulqrum is based on C++17 and requires having OpenMP 3.0+. Getting OpenMP is straightforward on Linux but does require installing LLVM via Homebrew on OSX.

Note that the runtime of Fulqrum is compiler dependent. In practice the clang compiler works better than gcc, and vendor versions of clang, such as the Intel and AMD compilers, show further gains in performance.

Build files locally

For testing we only require building the source files locally using:

python setup.py build_ext --inplace

you can add also use env flags on Linux and OSX for such things as specifying the compiler, e.g. CC=clang CXX=clang++ or setting the target architecture like FQ_ARCH=znver4.

Parallel builds can be activated using the FQ_BUILD_PARALLEL=N flag where N is the number of threads to run.

Installation on Linux

Installation on Linux is simple:

pip install .

Installation on OSX

On OSX, to get OpenMP, one should install llvm using homebrew:

brew install llvm

Then installation of Fulqrum with openmp can be accomplished using a call like:

CC=clang CXX=clang++ pip install .

Installation on Windows

Windows is currently not supported and there is currently no plan to do so.