Using GQCP(y)

After you have installed GQCP, you can either interface directly with GQCP through C++ or use its Python bindings.

Using GQCP through CPP

Hello GQCP: source file

Given the following XYZ file

3

O          0.00000       -0.07579        0.00000
H          0.86681        0.60144        0.00000
H         -0.86681        0.60144        0.00000

a prototypical Hello GQCP driver driver.cpp is given by

#include <iostream>
#include <gqcp.hpp>

int main(int argc, char * argv [] ) {
    const auto water_molecule = GQCP::Molecule::ReadXYZ("../water.xyz");  // creates a neutral molecule
    std::cout << "Hello GQCP!" << std::endl;
    std::cout << water_molecule << std::endl;
    return 0;
}

Hello GQCP: build stage

We have packaged GQCP into its own CMake modules, such that it can be easily found

find_package(gqcp REQUIRED)

and linked

target_link_libraries(${EXTERNAL_PROJECT_TARGET} PUBLIC GQCP::gqcp)

Given the driver.cpp source file detailed above, the following CMakeLists.txt should allow you to compile that code

cmake_minimum_required(VERSION 3.13 FATAL_ERROR)
project(driver VERSION 0.1.0 LANGUAGES CXX)

find_package(gqcp REQUIRED)

add_executable(driver driver.cpp)
target_link_libraries(driver PUBLIC GQCP::gqcp)

given that you pass the location of GQCP during the CMake build procedure. On the Docker platform, this translates into

mkdir build && cd build
cmake .. -DCMAKE_PREFIX_PATH=/usr/local/miniconda3/
make -j${NCPUS}

with ${NCPUS} the number of CPUs that can be reserved for compilation. After compilation, you can find the driver.x executable in the build folder.

Using GQCP through Python bindings: GQCPy

In contrast to using GQCP through C++, using the provided Python bindings is as easy as

import gqcpy
import numpy as np