''' Purpose: determine a rough estimate of the geocenter of the
        continental USA
'''

# get access to web-based data support
import url

# specify dataset web location
CSV_WEB_FOLDER = 'http://www.cs.virginia.edu/~cs1112/datasets/csv/'

USA_DATASET    = CSV_WEB_FOLDER + 'continental-usa.csv' # Where our dataset is

# get the dataset of interest
dataset = url.get_csv_dataset( USA_DATASET )    # Will turn into a dataset. All items are strings.

# determine webfile header and location data

# determine geocenter

lats = []       # list for our latitudes
longs = []      # list for our longitudes

for row in dataset:             # This line gets each row element in our dataset from above

    # Pick off the latitude and longitude
    zip_code, city, state, latitude, longitude = row    # row has 5 elements, so they will each go to a variable

    # Alternatively row[3] is the latitude &  row[4] is the longitude

    # Convert to floats
    latitude = float( latitude )
    longitude = float( longitude )

    # Add to our lists
    lats.append( latitude )
    longs.append( longitude )

# Get min latitude and min longitude
min_lat = min( lats )   # gets the minimum element from the list of latitudes
min_long = min( longs )

# Get max latitude and max longitude
max_lat = max( lats )
max_long = max( longs )

# Average for the geocenter :D
average_lat = ( min_lat + max_lat ) / 2
average_long = ( min_long + max_long ) / 2

print( average_lat, average_long )