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Chapter 8 Getting There Quicker with Geospatial Technology
from your house to the shoe store, then the shortest path from the shoe
store to the music store, and finally the shortest path from the music
store to the book store.
2. Finding the shortest path when you can arrange the order of visiting the
stops: For instance, if the book store and the shoe store are near each
other, it makes sense to rearrange your travels, so you visit them one
after the other, and then drive to the music store.
Geospatial technology applications can help determine some solutions
to both of these scenarios. To visit stops in a pre-determined order, the system will find the shortest route (of all possible routes) from the origin to
the first stop, then choose the shortest route to travel from the first stop to
the second stop, and so on. An example of this in vehicle-navigation systems is being able to set up a “Via Point” (another stop) between your origin and final destination—the device will then calculate the route from the
origin (or current location) to the Via Point, then from the Via Point to the
final destination.
With the ability to rearrange the order of stops, a system will evaluate
options by changing the order of visiting stops to produce the overall shortest route. See Figure 8.8 for an example of how the “shortest path” changes
between visiting stops in order as opposed to being able to rearrange the order
of visiting the stops. Additional constraints can be placed on the problem—for
instance, you may have to return home (the starting point) after visiting all
of the stops. When rearranging stops, the starting point then becomes the last
stop and may affect how the reordering is done. Conversely, you may want
There are many online applications available for
creating a map of an address and then generating
a shortest path and directions from that address to
another one. Examine the functionality of some of
the following online mapping sites:
1. Google Maps: http://maps.google.com
2. MapQuest: http://www.mapquest.com
3. Yahoo! Maps: http://maps.yahoo.com
4. Bing Maps: http://www.bing.com/maps
Try inputting the same pair of locations (origin
and destination) into each Web service and compare
the shortest paths and routes they generate (some
of them may be similar, some may be different, and
some will likely give you more than one option for
the ”shortest path”). In addition, the services will
also allow you to alter the route interactively by
moving and repositioning junctions of the path, so
you can tailor the route more to your liking. Set up
a shortest route, then position your cursor at junctions along the path—you can move the nodes and
reset the routes. How do they change in terms of
time and distance by remaking them?
Also, for each service, note the source of the
maps being generated (usually in small text at the
bottom of the map). What is the copyrighted source
of the maps?
Hands-on Application 8.4
Online Mapping and Routing Applications and Shortest Paths
Chapter 8 Getting There Quicker with Geospatial Technology
from your house to the shoe store, then the shortest path from the shoe
store to the music store, and finally the shortest path from the music
store to the book store.
2. Finding the shortest path when you can arrange the order of visiting the
stops: For instance, if the book store and the shoe store are near each
other, it makes sense to rearrange your travels, so you visit them one
after the other, and then drive to the music store.
Geospatial technology applications can help determine some solutions
to both of these scenarios. To visit stops in a pre-determined order, the system will find the shortest route (of all possible routes) from the origin to
the first stop, then choose the shortest route to travel from the first stop to
the second stop, and so on. An example of this in vehicle-navigation systems is being able to set up a “Via Point” (another stop) between your origin and final destination—the device will then calculate the route from the
origin (or current location) to the Via Point, then from the Via Point to the
final destination.
With the ability to rearrange the order of stops, a system will evaluate
options by changing the order of visiting stops to produce the overall shortest route. See Figure 8.8 for an example of how the “shortest path” changes
between visiting stops in order as opposed to being able to rearrange the order
of visiting the stops. Additional constraints can be placed on the problem—for
instance, you may have to return home (the starting point) after visiting all
of the stops. When rearranging stops, the starting point then becomes the last
stop and may affect how the reordering is done. Conversely, you may want
There are many online applications available for
creating a map of an address and then generating
a shortest path and directions from that address to
another one. Examine the functionality of some of
the following online mapping sites:
1. Google Maps: http://maps.google.com
2. MapQuest: http://www.mapquest.com
3. Yahoo! Maps: http://maps.yahoo.com
4. Bing Maps: http://www.bing.com/maps
Try inputting the same pair of locations (origin
and destination) into each Web service and compare
the shortest paths and routes they generate (some
of them may be similar, some may be different, and
some will likely give you more than one option for
the ”shortest path”). In addition, the services will
also allow you to alter the route interactively by
moving and repositioning junctions of the path, so
you can tailor the route more to your liking. Set up
a shortest route, then position your cursor at junctions along the path—you can move the nodes and
reset the routes. How do they change in terms of
time and distance by remaking them?
Also, for each service, note the source of the
maps being generated (usually in small text at the
bottom of the map). What is the copyrighted source
of the maps?
Hands-on Application 8.4
Online Mapping and Routing Applications and Shortest Paths