ニューラルネットワークに囲碁を学習させようとしている．前回はとりあえずニューラルネットワークを使ってみるということをしてみた．
学習を始めるには，学習用のデータが必要となる．棋譜はSGFファイル形式でインターネットに転がっているが，人間の棋譜は半端なところで終わっている．どこが自分の地かということにすでに経験的判断が必要になる．とくに日本ルールは終局がwell-definedでないという話がでるほど，終局が難しい．最初のステップとして，終局図から目算できるようにさせたい．
したがって，終局状態の配置と領地の分布の対応のデータが必要なのだが，これを得るのに結構苦労した．
終局しているのだから，モンテカルロ法のプレイアウトのように適当に打っても結果は変わらないのではないかと思ったら全然そんなことはなかった．わざわざプレイアウトをするコード書いたのだけど，意味なかった．
結局，GNU Goで終局状態から更に局面を進めることにした．以下のシェルスクリプトで結果が誰の目にも明らかになるまで局面を進めてくれる．
sgf=`cat $1` prev=0 while true; do sgf=`echo $sgf | gnugo --chinese-rules --play-out-aftermath --capture-all-dead -l - -o - 2> tmp` cat tmp 1>&2 play=`cat tmp | awk '{print $4}'` if [ $play = "PASS" ]; then if [ $prev -eq 1 ]; then break; fi prev=1 else prev=0 fi done echo $sgf
before.sgfに局面が追加されたものafter.sgfに出力される．
$ sh playout.sh before.sgf > after.sgf
左がboforeで右がafter
ここから，さらに地を塗り潰したものが最終的に欲しいものだ．地を塗りつぶすコードも，作りかけで汚いが参考までに貼っておく．モンテカルロ法のプレイアウトの痕跡も残っている．参考にあるモンテカルロ法のサンプルコードをPythonで書きなおしただけだけど．
参考
コンピュータ囲碁 〜 モンテカルロ法の理論と実践 〜 実践編のサンプル一覧
地を埋めるコード
import copy import random import sys EMPTY = 0 BLACK = 1 WHITE = 2 WALL = 3 def flip_color(color): return WHITE if color == BLACK else BLACK class GoError(Exception): pass class SuicidePlayError(GoError): pass class KoError(GoError): pass class EyeBreakingError(GoError): pass class StoneAlreadyExistsError(GoError): pass class Board(): SIZE = 19 WIDTH = SIZE + 2 DIR4 = [+1, -1, +WIDTH, -WIDTH] def __init__(self): self.board = [ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, ] self.teban = BLACK self.hama = [0, 0] self.ko = 0 self.komi = 6.5 def get_teban(self): return self.teban def get_color(self, tz): return self.board[tz] def count_dame(self, tz): check_board = [] color = self.board[tz] def count_dame_sub(tz_, dame, stone): check_board.append(tz_) stone += 1 for direction in self.DIR4: z = tz_ + direction if z in check_board: continue if self.board[z] == 0: check_board.append(z) dame += 1 if self.board[z] == color: dame, stone = count_dame_sub(z, dame, stone) return dame, stone return count_dame_sub(tz, 0, 0) def kesu(self, tz, color): self.board[tz] = 0 for direction in self.DIR4: z = tz + direction if self.board[z] == color: self.kesu(z, color) def is_eye(self, z, color): if self.board[z] != EMPTY: return False num_friend = 0 num_wall = 0 for direction in self.DIR4: c = self.board[z + direction] if c == color: num_friend += 1 elif c == WALL: num_wall += 1 if num_friend + num_wall == 4: return True else: return False def move(self, play, color, allow_eyebreak=True): if play == 0: self.ko = 0 self.teban = flip_color(self.teban) return around_dame = [0, 0, 0, 0] around_stone = [0, 0, 0, 0] around_color = [0, 0, 0, 0] enemy_color = flip_color(color) num_empty = 0 num_wall = 0 num_safe_friend = 0 take_sum = 0 for i in range(4): z = play + self.DIR4[i] c = self.board[z] if c == 0: num_empty += 1 continue if c == 3: num_wall += 1 continue dame, stone = self.count_dame(z) around_dame[i] = dame around_stone[i] = stone around_color[i] = c if c == enemy_color and dame == 1: take_sum += stone ko_kamo = z if c == color and dame >= 2: num_safe_friend += 1 # Suiside play if take_sum == 0 and num_empty == 0 and num_safe_friend == 0: raise SuicidePlayError(get_xy(play)) # Ko if play == self.ko: raise KoError(get_xy(play)) # Eye (Not illegal) if num_wall + num_safe_friend == 4 and not allow_eyebreak: raise EyeBreakingError(get_xy(play)) # Stone already exists if self.board[play] != EMPTY: raise StoneAlreadyExistsError(get_xy(play)) for i in range(4): z = play + self.DIR4[i] if (around_color[i] == enemy_color and around_dame[i] == 1 and self.board[z] != EMPTY): # Stones are takable self.kesu(z, enemy_color) self.hama[color - 1] += around_stone[i] # Put a stone self.board[play] = color # Judge if ko or not dame, ishi = self.count_dame(play) if take_sum == 1 and ishi == 1 and dame == 1: self.ko = ko_kamo else: self.ko = 0 self.teban = flip_color(self.teban) def print_board(self): strs = [". ", "@ ", "O "] for y in range(self.SIZE): for x in range(self.SIZE): z = get_z(x, y) s = strs[self.board[z]] print s, print "" def get_z(x, y): assert 0 <= x < Board.SIZE assert 0 <= y < Board.SIZE return (y + 1) * Board.WIDTH + (x + 1) def get_xy(z): assert 0 <= z < Board.WIDTH ** 2 if z == 0: return (0, 0) y = z / Board.WIDTH x = z - y * Board.WIDTH return (x, y) def playout(color, board): prev_play = 0 # Previous play loop_max = Board.SIZE ** 2 for _ in range(loop_max): # Include all empty points to candidates candidates = [] for y in range(Board.SIZE): for x in range(Board.SIZE): z = get_z(x, y) if board.get_color(z) != EMPTY: continue candidates.append(z) while True: if candidates: play = random.choice(candidates) else: play = 0 # Pass play try: board.move(play, color, False) break except StoneAlreadyExistsError: # Sanity check raise except GoError: pass candidates.remove(play) # Continuous pass play if play == 0 and prev_play == 0: break prev_play = play color = flip_color(color) def fillout_territory(board): # Include all empty points to candidates candidates = [] for y in range(Board.SIZE): for x in range(Board.SIZE): z = get_z(x, y) if board.get_color(z) != EMPTY: continue candidates.append(z) while candidates: z = random.choice(candidates) for direction in Board.DIR4: c = board.get_color(z + direction) if c == BLACK or c == WHITE: board.board[z] = c candidates.remove(z) break score_black = 0 score_white = 0 for y in range(Board.SIZE): for x in range(Board.SIZE): z = get_z(x, y) c = board.get_color(z) if c == BLACK: score_black += 1 elif c == WHITE: score_white += 1 return score_black - score_white - board.komi class Sgf(): tesuu_now = 0 def __init__(self, sgf_str): sgf_str = sgf_str.lstrip('(') sgf_str = sgf_str.rstrip(')') sgfdatas = sgf_str.split(';')[1:] header = sgfdatas[0].split(']')[:-1] self.props = {} header = map(lambda s: s.split('['), header) map(lambda l: self.props.update({l[0]:l[1]}), header) self.plays = sgfdatas[1:] def get_result(self): result_str = self.props['RE'] result = float(result_str[1:]) if result_str[0] == 'W': result = - result return result def get_komi(self): return float(self.props['KM']) def get_tesuu(self): return len(self.plays) def next_play(self): if self.tesuu_now >= len(self.plays): return '', -1, -1 # When the game is finished color_str, play_str = self.plays[self.tesuu_now].split(']')[0].split('[') if play_str == '': # Pass play_x = -1 play_y = -1 else: play_x = ord(play_str[0]) - ord('a') play_y = ord(play_str[1]) - ord('a') self.tesuu_now += 1 return color_str, play_x, play_y def apply_sgf(board, sgf_str, tesuu=-1): s = Sgf(sgf_str) b.komi = s.get_komi() if tesuu < 0: tesuu = s.get_tesuu() for _ in range(tesuu): color_str, play_x, play_y = s.next_play() if color_str == 'B': color = BLACK elif color_str == 'W': color = WHITE else: raise TypeError('A stone color of a play is imvalid: ' + color_str) if play_x >= 0 and play_y >= 0: play = get_z(play_x, play_y) else: play = 0 board.move(play, color) def append_sgf(sgf_str, board_old, board_new): strs = [sgf_str.strip().rstrip(')')] for y in range(Board.SIZE): for x in range(Board.SIZE): z = get_z(x, y) if board_new.board[z] != board_old.board[z]: c = 'B' if board_new.board[z] == BLACK else 'W' strs.append(';%s[%s%s]C[fillout territory]' % (c, chr(x + ord('a')), chr(y + ord('a')))) strs.append(')') return ''.join(strs) if __name__ == '__main__': sgf_str = sys.stdin.read() b = Board() apply_sgf(b, sgf_str) b_copy = copy.deepcopy(b) score = fillout_territory(b) print append_sgf(sgf_str, b_copy, b)
