help traveltime                                                (SJ11-1: dm0053)
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Title

    traveltime -- Find travel time between points using Google Maps


Syntax
        traveltime, start_x(varname) start_y(varname) end_x(varname)
                 end_y(varname) [mode(varname) km]


Description 

    traveltime uses Google Maps to generate travel time and calculate
    distance between sets of points.  start_x(), start_y(), end_x(), and
    end_y() contain the latitude and longitude of the origin and destination
    points, in decimal degrees.  Choice of travel mode can also be specified
    with the mode() option.

    traveltime generates the variables days, hours, mins, and
    traveltime_dist. The first three variables correspond to the number of
    days, hours, and minutes it takes to travel between the origin and
    destination.  For example, if the travel time between origin and
    destination is 1 day, 7 hours, and 37 mins, the values for days, hours,
    and mins would be 1, 7, and 37, respectively.  The variable
    traveltime_dist is the distance between the sets of points.  The
    traveltime_dist will be reported in miles unless the kilometers (km)
    option is specified.


Options

    start_x(varname) specifies the variable containing the geocoded x
        coordinate of the starting point.  start_x() is required.

    start_y(varname) specifies the variable containing the geocoded y
        coordinate of the starting point.  start_y() is required.

    end_x(varname) specifies the variable containing the geocoded x
        coordinate of the destination.  end_x() is required.

    end_y(varname) specifies the variable containing the geocoded y
        coordinate of the destination.  end_y() is required.

    mode(varname) specifies the mode choice of the trip.  The values are set
        to 1 for car, 2 for public transportation, and 3 for walking.  The
        default mode is car.

    km specifies that traveltime_dist be reported in kilometers rather than
        in miles (the default).


Note and warning 

    traveltime requires that the latitude and longitude of the origin and
    destination points be in decimal degrees.  This task can be accomplished
    using the geocode command.

    Google Maps has a daily limit of maximum queries that is not currently
    known.  If you use traveltime, you should use it in accordance with
    Google's terms of use.  For more information on the terms of service of
    Google Maps, see http://code.google.com/apis/maps/terms.html.


Example

    . traveltime, start_x(begin_long) start_y(begin_lat) end_x(end_long)
        end_y(end_lat) mode(autochoice)
 


Authors

    Adam Ozimek
    Econsult Corporation
    Philadelphia, PA
    ozimek@econsult.com
      
    Daniel Miles
    Econsult Corporation
    Philadelphia, PA
    miles@econsult.com
    

Also see

    Article:  Stata Journal, volume 11, number 1: dm0053

       Help:  geocode (if installed)