def populate_from_spreadsheet(self, input_file_name):
"""
Grab voter data from the given spreadsheet
(prepared by create_spreadsheet_from_voter_dictionary in create-voter-spreadsheet.py)
and populate the Contest with the relevant Voters and Entries.
"""
if self.verbose:
print(f"Populating contest with voter data from {input_file_name}...",
end="", flush=True)
with open(input_file_name, "r", newline="") as spreadsheet:
reader = csv.reader(spreadsheet, delimiter=",")
header = next(reader)
entry_names = header[1:]
# If there n Entries, each voter can assign at most n distinct rankings.
# (Really the number of Entries may be more than the number of distinct rankings.
# For example, a poll could ask users to vote for the top 3 Entries out of 10.
# It's fine to overestimate the number of distinct rankings though. It'll just lead to
# some wasted space in each Voter, which doesn't really matter.)
num_distinct_rankings = len(entry_names)
# construct Entries
for entry_name in entry_names:
# self.entries[i] contains the entry from column i+1
# (not column i because the leftmost column contains user info, not entry info)
self.entries.append(Entry(entry_name))
# construct Voters and record their votes
for row in reader:
voter_name = row[0]
# voter_rankings[i] contains the voter's ranking for entry self.entries[i]
voter_rankings = row[1:]
voter = Voter(voter_name, num_distinct_rankings)
for i, ranking in enumerate(voter_rankings):
if ranking:
# the ranks are stored in user_rankings as a list of strings, so cast them
# to ints for use as indexes
voter.rank(self.entries[i], int(ranking))
self.voters.append(voter)
if self.verbose:
print(" done.")
