HW4EC.txt

EXTRA CREDIT
The DataAnalysisStationTrip has the following method to answer the extra credit questions:

getLeastPopularEndStation(): this method returns the end station with minimum trips, by traversing through all stations listed in station data
it is found that some stations do not have any trips taken from or to them, as start and end. It returns the first station with 0 trips.

getLeastEndPopularStation(): this method only checks end stations in the trip data and returns the station with minimum trip among those.
HashMap is used to get key as station and value as number of times they were end stations.
We then loop through each key to get the one with minimum value and return that station as the least popular station.

WILDCARD:getNumTripsWithDurLess(int time): this method returns the count of number of trips which had duration less that the specified.

getNumPairsOfCloseStations():returns the number of pairs of close stations using formula described: diff lat+ diff long/2< 0.02
if the difference between latitude and longitude, the sum divided by 2 is less than 0.02 of start and end station for a trip,
then we consider the two stations to be close to each other.
We put an additional check by creating an ArrayList of arraylist of integers, which contain arraylist of stations pairs,
if the stations pair already exist in the list, we do not increment the count of such pairs.
The arrayList of station pairs is checked for the flipped case as well. 
i.e if (1,2) is present or (2,1) is present already, we do not consider those again.

1.No of stations close to each other are:3983
We use getPairsOfCloseStations() of DataAnalysisStationTrip object to get the number of pairs of stations that are close to each other

2.The least popular endStation:Broad & Fitzwater
We use getLeastPopularEndStation() of DataAnalysisStationTrip object to get the station from stationData with least number of trips as end stations.
The result is the station name of a station which has 0 trips as end station. This can be seen from the final report.

2.The least popular endStation2:15th & Kitty Hawk
We use getLeastEndPopularStation() of DataAnalysisStationTrip object to get the end station with least number of trips.
We only look at endStations from trip data, not looking at station data at all.
This returns the station among end stations with least no of trips.

3.Wildcard:No. of trips with duration less that 10 min:89327
We use getTripsWithDurLess(10) of DataAnalysisStationTrip object , with parameter as 10 to represent time,to get the number of trips in the trip data with duration less that 10 min.