route_data <- data.table(route = c("Seattle>NewDelhi>Patna>Motihari", "Seattle>NewDelhi>Motihari","Seattle>Hyderabad>NewDelhi>Patna>Motihari"),
                         travel_type = c("business_meeting", "casual_trip","office_meeting"),
                         leg1_time_hr = c(18.0,18.0,18.0),
                         leg2_time_hr = c(2,18,2.25),
                         leg3_time_hr = c(4.0,NA,1.75),
                         leg4_time_hr = c(NA,NA,4.0))

example_nested_data <- data.table(leg = c("Seattle>Hyderabad", "Hyderabad>NewDelhi","NewDelhi>Patna","Patna>Motihari"),
                         leg_num = c(1,2,3,4),
                         leg_transit_time_hr = c(18.0,2.25,1.75,4.0)
                         )