# QuEBApp

A python module to find communities in complex quantum systems2014-02-16

Quantum Effects Based Approach to community detection. This sofware compute the community structure of a Quantum System based on its Hamiltonian, on the preferred basis.

For details see: here

## Requirements

- Python3 (it should work in python2 too, not sure about that)
- matplotlib (only for dendrogram plots)
- numpy, scipy

## Install

Clone the repository somewhere

`git clone https://bitbucket.org/maurofaccin/quebapp.git`

go to the folder

`cd quebapp`

install (use `--user`

if you don't have root privileges or you want a local
install)

`./setup.py install [--user]`

## Usage

Use `quebapp -h`

for help.

```
usage: quebapp [-h] [--edgelist] [-0]
[-t {fidelity,transport,purity}] [-d]
network
QuEBApp: Quantum Community Detection
positional arguments:
network Network file [default=Hamiltonian matrix]
optional arguments:
-h, --help show this help message and exit
--edgelist Read Hamiltonian as list of edges [i j
weight(optional)]
-0, --time0 Closeness measure with short-time limit [default:
long-time limit]
-t {fidelity,transport,purity}, --type {fidelity,transport,purity}
Use a specific closeness measure [default: fidelity]
-d, --dendrogram Outputs the resulting dendrogram and modularity
```

The network representing the quantum system needs to be a Hermitian matrix (the Hamiltonian). It can be given in matrix form:

```
h_11 h_12 h_13 ...
h_21 h_22 h_23 ...
h_31 h_32 h_33 ...
... ... ... ...
```

with `h_ij`

complex conjugate of `h_ji`

.
The matrix can be given as an edge list:

```
i j h_ij
... ... ...
```

where `i`

and `j`

are indexes and `h_ij`

the Hamiltonian entry (`h_ji`

will
be computed automatically).

## License

Copyright: Mauro Faccin (2014)

QuEBApp 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.

QuEBApp 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.

Check LICENSE.txt for details.