# 2. Getting Started

This page describes how to get started with AequilibraE.

Note

Although AequilibraE is under intense development, you don’t need to expect important API changes, but you should check for new features often.

## 2.1. Installation

1. Install Python 3.5, 3.6 or 3.7. We recommend Python 3.7 as of late 2019.

2. Install AequilibraE

    pip install aequilibrae

### 2.1.1. Dependencies

Aequilibrae relies on a series of compiled libraries, such as NumPy and Scipy. If you are working on Windows and have trouble installing any of the requirements, you can look at Christoph Gohlke’s wonderful repository of compiled Python packages for windows.

#### 2.1.1.1. OMX support

AequilibraE also supports OMX starting on version 0.5.3, but that comes with a few extra dependencies. Installing openmatrix solves all those dependencies:

    pip install openmatrix

#### 2.1.1.2. Spatialite

Although the presence of Spatialite is rather obiquitous in the GIS ecosystem, it has to be installed separately from Python or AequilibraE.

##### 2.1.1.2.1. Windows

Spatialite does not have great support on Python for Windows. For this reason, it is necessary to download Spatialite for Windows and inform AequilibraE of its location.

One can download the 64Bit version of SpatiaLite or navigate to the SpatiaLite website to download the appropriate version.

After unpacking the zip file into its own folder (say D:/spatialite), one can update the AequilibraE parameter file with the location of spatialite by using the Parameters module as follows:

    from aequilibrae import Parameters

    fldr = 'D:/spatialite'

    p = Parameters()
    p.parameters['system']['spatialite_path'] =  fldr
    p.writeback()

It is not possible to use Spatialite with AequilibraE on windows by simply editing environment variables.

##### 2.1.1.2.2. Linux

On linux it is possible to install Spatialite by simply using apt-get

    sudo apt-get install libsqlite3-mod-spatialite
    sudo apt-get install -y libspatialite-dev

##### 2.1.1.2.3. MacOS

On MacOS one can use brew as per this answer on StackOverflow.

    brew install libspatialite

## 2.2. Hardware requirements

AequilibraE’s requirements depend heavily of the size of the model you are using for computation. The most important things to keep an eye on are:

- Number of zones on your model (size of the matrices you are dealing with)

- Number of matrices (classes you are dealing with)

- Number of links and nodes on your network (far less likely to create trouble)

Substantial testing has been done with large real-world models (up to 6,000 zones) and memory requirements did not exceed the traditional 32Gb found in most modelling computers these days. In most cases 16Gb of RAM is enough even for large models. Parallelization is fully implemented for graph computation, and can make use of as many CPUs as there are available in the system when doing traffic assignment.