.. resources ==================================== Resources for Computing Travel Cost ==================================== | The spatial access measures depend on travel times or distances between origins and destinations. If you only need distances between origins and destinations, the package will calculate Euclidean distances for your projected data. If you need travel times for a specific travel mode, you need to generate these so-called travel time (or travel cost) matrices from other sources. Explore and Download Pre-Computed Travel Times ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | Since this is computationally expensive and non-trivial to implement at scale, we pre-computed driving times between tracts within 100 km (62 miles) of each other for the whole US. Explore the map of driving times between a selected Census tract and all tracts within 100 km (62 miles) by clicking around or entering an address. You can also download these results for driving or transit. .. raw:: html
Web Service to explore and download travel times between tracts
| | In addition to driving times between tracts within 100 km, you can access matrices for walking, transit or driving times between blocks or tracts for the 20 largest cities in the US. Note that there are some null values -- these are usually due to population-weighted centroids that could not be snapped to nearby road networks, missing GTFS feeds for transit, or feeds that do not span more than one Census tract, as in less urban areas. This page hosts point-to-point distance matrices generated by the Center for Spatial Data Science. The matrices come as bzipped CSVs, structured using the `format shown here `_. Cities are listed according to their containing county code. The origins for each distance matrix are the population-weighted centroids that lie within each county, and the destinations are any population-weighted centroids that lie within 100 km of the buffered county. For a full list of origin and destination locations + attached populations, see the `CSDS Box folder `_. .. raw:: html
CITY NAME COUNTY GEOID
National All Tracts Tracts Tracts
New York City (Manhattan) 36061 Tracts / Blocks Tracts / Blocks Tracts
New York City (Brooklyn) 36047 Tracts / Blocks Tracts / Blocks Tracts
New York City (The Bronx) 36005 Tracts / Blocks Tracts / Blocks Tracts
New York City (Staten Island) 36085 Tracts / Blocks Tracts / Blocks Tracts
New York City (Queens) 36081 Tracts / Blocks Tracts / Blocks Tracts
Los Angeles 06037 Tracts / Blocks Tracts / Blocks Tracts
Chicago 17031 Tracts / Blocks Tracts / Blocks (Part 1)
Blocks (Part 2) 		Tracts
Houston 48201 Tracts / Blocks Tracts / Blocks Tracts
Phoenix 04013 Tracts / Blocks Tracts / Blocks Tracts
Philadelphia 42101 Tracts / Blocks Tracts / Blocks Tracts
San Antonio 48029 Tracts / Blocks Tracts / Blocks Tracts
San Diego 06073 Tracts / Blocks Tracts / Blocks Tracts
Dallas 48113 Tracts / Blocks Tracts / Blocks Tracts
San Jose 06085 Tracts / Blocks Tracts / Blocks Tracts
Austin 48453 Tracts / Blocks Tracts / Blocks Tracts
Jacksonville 12031 Tracts / Blocks Tracts / Blocks Tracts
Fort Worth 48439 Tracts / Blocks Tracts / Blocks Tracts
Columbus 39049 Tracts / Blocks Tracts / Blocks Tracts
San Francisco 06075 Tracts / Blocks Tracts / Blocks Tracts
Charlotte 37119 Tracts / Blocks Tracts / Blocks Tracts
Indianapolis 18097 Tracts / Blocks Tracts / Blocks Tracts
Seattle 53033 Tracts / Blocks Tracts / Blocks Tracts
Denver 08031 Tracts / Blocks Tracts / Blocks Tracts
Washington D.C. 11001 Tracts / Blocks Tracts / Blocks Tracts
| Some of the matrices linked here are very large when unzipped (up to 100 GB). We have created an example bash script demonstrating how to extract a smaller portion of a larger matrix using bzcat and awk. The script and a short example can be found `here `_. These matrices were generated using `OpenTripPlanner `_ (OTP) and Docker. The necessary containers can be found `here `_ and `here `_ and are also available on `DockerHub `_. All matrices were generated with the following settings using all land-based GTFS feeds available in a given county buffer, including e.g. buses, subways, and lightrail (no ferries are included). .. raw:: html
Setting Tract / Block
Max Travel Time Tract Inf Inf Inf
Max Walking Dist. Tract 5 km 5 km N/A
Walking Speed Tract ~3 mph ~3 mph N/A
Departure Time Tract N/A Noon, nearest Monday N/A
Max Travel Time Block 90 min. 90 min. N/A
Max Walking Dist. Block 5 km 5 km N/A
Walking Speed Block ~3 mph ~3 mph N/A
Departure Time Block N/A Noon, nearest Monday N/A

Created by: Dan Snow, MPP | Sept. 2019

| Compute your Own Travel Times ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | If you need to compute customized cost matrices, there are several options. This table lists some of them: .. raw:: html
Name Installation Notes
pgRouting docker Good for driving, open-source and free, PostgreSQL/postgis and OpenStreetMap (OSM)
OSRM install / R / docker Best for driving, OSM, open-source and free, customized travel parameters, C++
Open Trip Planner docker routing / resources / DockerHub Best for transit, open-source and free, customized travel parameters, Java
Valhalla install Multi-modal, OSM, open-source, for fee at scale, Python
Pandana install Good for driving and walking, OSM, open-source and free, part of UrbanSim, Python
Graphhopper install Multi-modal, OSM, open-source, for fee at scale, Python
Spatial Access Package install / notebooks Best for walking, OSM, scales well, open-source and free, includes spatial access metrics, Python
e.g. dogr, R5 and gtfs-router dogr, R5, gtfs-router Selected R packages
Google Maps install Accurate multi-modal, customized travel parameters, commercial, expensive at scale
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