Quantum++
Version 0.8.2 - 20 May 2015
Quantum++ is a C++11 general purpose quantum computing library, composed solely of template header files. It uses the Eigen 3 linear algebra library and, if available, the OpenMP multi-processing library. For additional Eigen 3 documentation see http://eigen.tuxfamily.org/dox/. For a simple Eigen 3 quick ASCII reference see http://eigen.tuxfamily.org/dox/AsciiQuickReference.txt.
Quantum++ is not restricted to qubit systems or specific quantum information processing tasks, being capable of simulating arbitrary quantum processes. The main design factors taken in consideration were the ease of use, high portability, and high performance.
If you are interesting in contributing, please contact me. To contribute, you need to have a decent knowledge of C++ (preferably C++11), including templates and the standard library, a basic knowledge of quantum computing and linear algebra, and some working experience with Eigen 3.
Copyright (c) 2013 - 2015 Vlad Gheorghiu, vgheorgh AT gmail DOT com.
Quantum++ is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
Quantum++ is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with Quantum++. If not, see http://www.gnu.org/licenses/.
Building instructions
Configuration:
- Compiler: g++ version 4.8 or later (for good C++11 support)
- Eigen 3 library located in
$HOME/eigen
- Quantum++ library located in
$HOME/qpp
- MATLAB compiler
include header files:
/Applications/MATLAB_R2014b.app/extern/include
- MATLAB compiler
shared library files:
/Applications/MATLAB_R2014b.app/bin/maci64
Building without a build system
- Example file:
$HOME/qpp/examples/minimal.cpp
- Output executable:
$HOME/qpp/examples/minimal
- Must run the commands below from inside the directory
$HOME/qpp/examples
MATLAB support):
Release version (withoutg++ -pedantic -std=c++11 -Wall -Wextra -Weffc++ -fopenmp \
-O3 -DNDEBUG -DEIGEN_NO_DEBUG \
-isystem $HOME/eigen -I $HOME/qpp/include \
minimal.cpp -o minimal
MATLAB support):
Debug version (withoutg++ -pedantic -std=c++11 -Wall -Wextra -Weffc++ -fopenmp \
-g3 -DDEBUG \
-isystem $HOME/eigen -I $HOME/qpp/include \
minimal.cpp -o minimal
MATLAB support):
Release version (withg++ -pedantic -std=c++11 -Wall -Wextra -Weffc++ -fopenmp \
-O3 -DNDEBUG -DEIGEN_NO_DEBUG \
-isystem $HOME/eigen -I $HOME/qpp/include \
-I/Applications/MATLAB_R2014b.app/extern/include \
-L/Applications/MATLAB_R2014b.app/bin/maci64 \
-lmx -lmat minimal.cpp -o minimal
MATLAB support):
Debug version (withg++ -pedantic -std=c++11 -Wall -Wextra -Weffc++ -fopenmp \
-g3 -DDEBUG \
-isystem $HOME/eigen -I $HOME/qpp/include \
-I /Applications/MATLAB_R2014b.app/extern/include \
-L /Applications/MATLAB_R2014b.app/bin/maci64 \
-lmx -lmat minimal.cpp -o minimal
cmake
Building usingThe current version of the repository has a ./CMakeLists.txt
configuration file
for building examples using cmake.
To build an example using cmake,
I recommend an out-of-source build, i.e., from the root of the project
(where ./include
is located), type
mkdir ./build
cd ./build
cmake ..
make
The above commands build the relase version (default) executable qpp
,
from the source file ./examples/minimal.cpp
,
without MATLAB support (default),
inside the directory ./build
. To build a different configuration,
e.g. debug version with MATLAB
support, type from the root of the project
cd ./build
rm -rf *
cmake -DCMAKE_BUILD_TYPE=Debug -DWITH_MATLAB=ON ..
make
Or, to disable OpenMP support (enabled by default), type
cd ./build
rm -rf *
cmake -DWITH_OPENMP=OFF ..
make
To change the name of the example file, the location of the
Eigen 3
library or the location of MATLAB
installation, edit the ./CMakeLists.txt
file. See also ./CMakeLists.txt
for additional options. Do not forget to remove everything from
the ./build
directory before a fresh build!
Additional remarks
-
The C++ compiler must be C++11 compliant.
-
If using Windows, I recommend compiling under cygwin via cmake and g++. See also http://stackoverflow.com/questions/28997206/cygwin-support-for-c11-in-g4-9-2 for a bug related to lack of support for some C++11 math functions, and how to fix it. Quick fix: patch the standard library header file
<cmath>
using the provided patch./cmath_cygwin.patch
. -
If your compiler does not support OpenMP (as it is the case e.g with clang++), disable OpenMP in your build, as otherwise the linker may not find the gomp library.
-
If you run the program on OS X with MATLAB support, make sure that the environment variable
DYLD_LIBRARY_PATH
is set to point to the MATLAB compiler library location, see therun_OSX_MATLAB
script. Otherwise, you will get a runtime error likedyld: Library not loaded: @rpath/libmat.dylib
.-
I recommend running via a script, as otherwise setting the
DYLD_LIBRARY_PATH
globally may interfere with macports' cmake installation (in case you use cmake from macports). If you use a script, then the environment variable is local to the script and does not interfere with the rest of the system. -
Example of running script, run from inside the directory where the executable
qpp
is located:#!/bin/sh # Run Quantum++ under OS X with MATLAB support export DYLD_LIBRARY_PATH=$DYLD_LIBRARY_PATH:"/Applications/MATLAB_R2014b.app/bin/maci64" ./qpp
-
-
If you build a debug version with g++ under OS X and use gdb to step inside template functions you may want to add
-fno-weak
compiler flag. See http://stackoverflow.com/questions/23330641/gnu-gdb-can-not-step-into-template-functions-os-x-mavericks for more details about this problem.