Travel Times by Transportation Mode in Nairobi, Kenya

<p>This directory contains data files that describe travel times in<br> Nairobi, Kenya. &nbsp;Three different modes of transportation are included:</p> <p>&nbsp;- Walking, according to MapQuest and filled in with Google Maps where<br> &nbsp; &nbsp;MapQuest fails to find a route.</p> <p>&nbsp;- Driving, under normal traffic conditions.</p> <p>&nbsp;- Matatus, the informal public transportation network.</p> <p>The travel times are computed from a gridded origin location to a<br> collection of gridded destination locations. &nbsp;In the directories, each<br> file contains destination location times for a given origin location.<br> These are titled &lt;mode&gt;-###.csv. &nbsp;The CSV is organized from north to<br> south, along rows, and west to east, along columns. &nbsp;An additional<br> &lt;mode&gt;.csv file in each directory gives the organization of the<br> numbered files, again from north to south, along rows, and west to<br> east, along columns.</p> <p>There are also &quot;extended&quot; versions of each grid, with larger<br> destination grids for each origin point, formed by &quot;daisy-chaining&quot;<br> together the original destination grids.</p> <p>The directory also contains source files for working with the data:</p> <p>&nbsp;- calc_access.R shows how to calculate a simple mobility measure,<br> &nbsp; &nbsp;using the functions in tools_calc_access.R</p> <p>&nbsp;- tools_analyze.R are a more general set of functions for performing<br> &nbsp; &nbsp;arbitrary callback-based operations on the travel time data.</p> <p>&nbsp;- tools_calc_access.R contains underlying functions for setting up<br> &nbsp; &nbsp;access to the grids and calculating access.</p> <p>&nbsp;- tools_map.R contains the grid origin and destination definitions<br> &nbsp; &nbsp;and functions for plotting.</p>