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CITY\ **hub**
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To represent a digital twin of a city and create pipelines for populating key information about the city, the CITY\ **hub** Python package utilizes two distinct concepts: the Central Data Model and Factories.

This Python package is used to create a digital twin representation of a city and generate the input file(s) required to
run energy-related simulations on that city. It can be run on NGCI servers to deliver real-time digital twin creation and
simulation via our CITY\ **layers** front-end or the WORKFLOW\ **launcher** front-end.
It is also provided as an importable Python library so that researchers with programming capabilities can include it in their work,
making digital twins of their use-cases and creating input files to run the simulations they need.

A defining aspect of the CITY\ **hub** is that it is intended to create digital twins across multiple domains (e.g. buildings, transport, energy systems, electricity supply, greenery,
and more), so allowing workflows to run simulations of these different domains to represent more complex urban scenarios. Driven by regional data, CITY\ **hub** homogenizes data from different sources
in a consistent and unified way allowing researchers, city planners, and policy makers to work with a consistent picture of the city for planning, analysis, and decision making.
Uniquely, the CITY\ **hub** supports exporting data in formats compatible with industry standard software such as EnergyPlus, ArcGIS, and more.

The primary use of CITY\ **hub** is academic, allowing researchers to create models with their own data and run simulations to generate results relevant to their research questions.
Due to its programmatic nature, researchers can run large numbers of simulation scenarios, over large datasets, allowing them to tackle complex research questions more easily.
Because CITY\ **hub** is multi-domain, researchers in one field can leverage the results of a simulated model in another field, without needing to be an expert in it.

The secondary use of CITY\ **hub** is supporting back-end applications aimed at helping urban stakeholders make smarter, accelerated decisions for sustainability and resilience, such as CITY\ **layers**.

.. figure:: ../images/hub-architecture.jpg
   :alt: Components that are part of the CITYhub library

   Components of the CIT\ **hub** library



.. toctree::
   :maxdepth: 1
   :caption: Contents

   architecture
   central_data_model
   import_factories
   export_factories
   catalog_factories
   tutorials/index