# Documentation for the density mode of MadGraph
Work In Progress

= Density mode
== Authors
V. Durupt
== Short description
Automatic computation of density matrices and quantum information observables. 
This page contains the technical description of the Python library Density_functions.py used for analysis.

== How to compute density matrices
This module of MadGraph5 allows to compute density matrices automatically in a user-friendly way. After having generated your process
{{{
generate YOUR_PROCESS
output
launch
}}}

you will be able to chose the type of run. To compute density matrices one must chose
{{{
reweight = density
}}}

The user is then asked to edit the different cards needed for the run. The information for the density matrices computation is given in the reweight_card. Examples for different benchmark processes are given in https://arxiv.org/abs/2510.17730.