Code problem - probably easy fix?

[deanhystad]

I don't really understand your code all that well, but does is this close to correct?

from datetime import datetime
from dataclasses import dataclass
import pandas as pd


@dataclass(order=True)
class Match:
    """Better than dictionary or lists for organizing data."""
    date: datetime
    player1: str
    player2: str
    score: float


@dataclass(order=True)
class Player:
    name: str
    rating: float = None


def load_matches(filename: str) -> tuple[list[Match], dict[str, Player]]:
    """Return list of match results and player ratings extracted from file."""
    # Collect match information in a list.
    df = pd.read_csv(filename)[["match_date", "player1", "player2", "actual_score"]]
    df["match_date"] = pd.to_datetime(df["match_date"])   # Convert timestamp to datetime
    df.sort_values(by=["match_date"])
    matches = [Match(*row) for index, row in df.iterrows()]

    # Extract initial player ratings from file.  Use first bp_score to
    # compute initial rating.
    df = pd.read_csv(filename)[["pb_date", "pb_player", "pb_score"]]
    df.dropna(subset=["pb_player"], inplace=True)   # Drop matches without bp_player
    df["pb_date"] = pd.to_datetime(df["pb_date"])   # Convert timestamp to datetime
    df.sort_values(by=["pb_date"])
    players = {}
    for index, (date, name, score) in df.iterrows():
        if score >= 1700000:
            rating = 10
        elif score >= 100000:
            rating = 5
        else:
            rating = 1
        if name not in players:
            players[name] = Player(name, rating)

    # Add other players from match data.
    for match in matches:
        if match.player1 not in players:
            players[match.player1] = Player(match.player1, 0)
        if match.player2 not in players:
            players[match.player2] = Player(match.player2, 0)

    return players, matches


def update_rating(match: Match, players: dict[str, Player]) -> None:
    if match.score < 0.5:
        players[match.player1].rating -= 1
        players[match.player2].rating += 1
    elif match.score > 0.5:
        players[match.player1].rating += 1
        players[match.player2].rating -= 1

# This does the first script. Somewhat.
players, matches = load_matches("matches_full.csv")

# This does the second script.  Well, it starts with the initial rating and
# adjusts based on match results.
for match in matches:
    update_rating(match, players)

for player in sorted(players.values(), key=lambda x: x.rating, reverse=True):
    print(player)

I left out the Glicko stuff. I don't understand it. I would make an error if I tried to implement it, and the important thing to demonstrate is how to get the initial rating from your first script and use it in your second script.