Section: New Software and Platforms

Wassily

Participants : Julien Alapetite, Jean-Yves Courtonne.

In collaboration with the association “Groupe de Réflexion sur les Empreintes Ecologiques Locales” (eco-data.fr ), STEEP contributes to the development of Wassily (in tribute to Wassily Leontief who first designed the relevant concepts), to perform input-output analyses applied to environmental issues (see section 4.2). The purpose of this software is to automatize most of the work of standard input-output analysis and to visualize the results in a user-friendly way in order to efficiently address the related key environmental questions.

The software is structured in three different modules:

• the database module stores all the input-output data coming from Eurostat, OCDE, Insee or other sources.

• the computation module performs the input-output calculations

• the visualization module displays the results in a synthetic manner.

The database module is based on the SQlite format and makes use of SQL to manipulate the various tables involved in the process. The goal of this module is to provide a normalized data interface for the computation module, from various types of input-output data which are often stored as Excel sheet on web sites.

The computation module is based on QT and C++ and deals mostly with matrix manipulation.

The visualization module is based on a JavaScript library called D3 and allows the user to visualize the results in a number of different ways, such as bar charts, pie charts, sankey diagrams to name a few. The integration between the C++ and JavaScript pieces of code is performed with QTScript.