Shogi notation

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Game record of a shogi game

Shogi notation is the set of various abbreviatory notational systems used to describe the piece movements of a shogi game record or the positions of pieces on a shogi board.

A game record is called a 棋譜 kifu in Japanese.

Recording moves[]

Western notation[]

The system used in English language texts to express shogi moves was established by and Glyndon Townhill in 1976 by the second issue of Shogi magazine.[1][a] A slightly modified version was used in Hosking (1996). It is derived from the algebraic notation used for chess, but differs in several respects.[2][3] A typical move might be notated P86 or P-8f. The notation format has the following 5 part structure:

1 2 3 4 5
piece (origin) movement destination (promotion)

An example using all 5 parts is S72x83+ or S7bx8c+. All parts are obligatory except for the origin and promotion parts. (Thus, most notation strings only contain 3 parts.) The origin part is only indicated when needed to resolve ambiguity. The promotion part is only needed when there is the possibility of promotion.

Western notation is not used in Japanese language texts, as it is no more concise than traditional notation with Japanese characters (kanji) and two ciphers which originated in the Edo period.

Piece[]

The first letter represents the piece moved. For instance, P is for Pawn. Below are the abbreviations used.

Abbreviation English Term Japanese
P pawn 歩
L lance 香
N knight 桂
S silver 銀
G gold 金
B bishop 角
R rook 飛
K king 玉/王

Promoted pieces are indicated by a + preceding the letter. For example, +P is a promoted pawn (と tokin), +R is a promoted rook (that is, a dragon 龍).

Some Japanese websites (such as 81Dojo) and Japanese authors use two different abbreviations for the promoted rook and promoted bishop in a way more similar to Japanese notation. Thus, D (for dragon) instead of +R and H (for horse) instead of +B. Additionally, a promoted pawn can be encountered as T (for tokin) instead of +P.

Ambiguity resolution: Origin coordinates[]

In cases where the moving piece is ambiguous, the starting square is added after the letter for the piece but before the movement indication.

For example, in diagrams below, Black has three golds which can move to square 78. Thus, simply notating G-78 is not enough to indicate the move. The three possible moves are distinguished via the origin specification as G77-78, G68-78, or G79-78.

Movement type[]

Following the abbreviation for the piece is a symbol for the type of move. There are 3 different indications:

Notation Symbol Movement Type
- simple movement
x capture (opponent's piece)
* or ’ drop (your own piece)

As examples, P-24 indicates moving one's pawn to the 2d square (without capture), Px24 indicates moving one's pawn to the 24 square and capturing the opponent's piece that was on 24, and P*24 indicates dropping one's pawn in hand to the previously empty 24 square. (Note the x indication is a significant departure from Japanese notation, which has no way of signaling whether a piece was captured.)

There is some variation for the drop symbol. A * (asterisk) is often used, but some books (e.g. Hosking 1997) use a ’ (apostrophe) instead. Thus, Hosking B’56 is equivalent to Hodges B*5f.[b]

The simple movement indication (the hyphen -) is not used by Hosking (1997) who does not use a movement symbol. Thus, Hosking P26 is equivalent to Hodges P-2f.

Destination coordinates[]

After the movement piece indication is the square on which the piece lands. This is indicated by a numeral for the file (1–9) and the rank (1–9), with 11 being the top right corner from Black's perspective and 99 being the bottom left corner. This is based on Japanese notation conventions.

Hosking differs from Hodges in that Hosking uses numerals for the rank notation whereas Hodges uses letters (a–i) for the rank.

Promotion status[]

If a move entitles the player to promote, then a + is added to the end if the promotion was taken or an = if it was declined. For example, Nx73= indicates an unpromoted knight capturing on 73 without promoting while Nx73+ indicates an unpromoted knight capturing on 73 and promoting. The promotion status is always omitted in situations where promotion is not possible. When promotion is possible, then the promotion status is obligatorily notated.

Other conventions[]

Game moves in western notation are always numbered (unlike Japanese game records). Additionally, what is numbered are pairs of two moves – the first move by Black, the second by White – instead of numbering each move by each player. This also differs from the Japanese system. For instance, three pairs of moves (or six individual moves) are numbered as 1.P-76 P-34 2.P-26 P-44 3.S-48 S-32. However, in the British Shogi magazine of the 1970s and 1980s, the pair number convention was not used for tsumeshogi problems, in which case the each player's move is number just as in the Japanese notation conventions.

Following western chess conventions, omitted moves are indicated with an ... ellipsis. As a consequence of the way moves are numbered in the western system, all moves by White are notated with an ellipsis prefix in texts. For example, ...P-55 indicates a move by White while P-55 indicates a move by Black. In handicap games, White plays first, so Black's first move is replaced by an ellipsis. For example, 1...G-32 2.P-76 G-72.

Unlike western chess, game states like check or checkmate are not typically notated. However, the use of question marks and exclamation points to indicate questionable and good moves, respectively, are occasionally used.

Japanese notation[]

Japanese notation (shown on the left, listed vertically) accompanying a 15-move checkmate (tsume) problem. Note the lack of numbered moves and the lack of both explicit dropped piece notation and capture notation. From the book 詰むや詰まざるや (Tsumu ya tsumazaru ya) (1975) by 伊藤宗看 (Sōkan Itō) [1706–1761], a shogi Meijin of the Edo period, and 門脇芳雄 (Yoshio Kadowaki).

The earliest way to indicate game records in Japan during the Edo period was to use descriptive sentences such as Open the bishop's diagonal, push the rook's pawn, close the bishop's diagonal and the like. Soon afterward, a notational system was developed which is mostly the same as what is used in the present day in Japan.[4]

Current standard[]

In Japanese notation, the notation string has the following five-part format:[5][6][7]

1 2 3 4 5
(player side) destination piece (movement) (promotion)

A typical move is indicated like ８六歩 (equivalent to western P-86). An example that uses all five parts is ☗８三銀引成 (which could be either S72-83+ or S72x83+ in western notation). The player's side information is optional and the movement and promotion indications are only used in order to resolve ambiguity.

Player's side[]

It is common for the White (gote) and Black (sente) player to be indicated at the beginning of the notation string with either black and white triangles (▲/△) or shogi-piece-shaped pentagons (☗/☖), such as ▲７六歩△３四歩▲２六歩△３二金 or ☗７六歩☖３四歩☗２六歩☖３二金. However, this is not obligatory: several books notate shogi moves without explicit indication of which player is making the moves. (See the adjacent image for an example.) In such cases, knowing which player the move refers to can be determined by the context in the book. This white/black convention is more common when the moves are not numbered (which is also optional to notate).

Destination coordinates[]

For the board's coordinates, the file is indicated with an Arabic numeral followed by the rank indicated with a Japanese numeral (instead of an Arabic number or letter like in the western system). For example, square 23 in Japanese notation is ２三.

Japanese numeral Japanese pronunciation Arabic equivalent
一 ichi １
二 ni ２
三 san ３
四 yon ４
五 go ５
六 roku ６
七 nana ７
八 hachi ８
九 kyū ９
同 dō or onajiku same

Earlier (for instance, in the Edo period), only Japanese numerals were used for both file and rank coordinate.

There is also an abbreviatory convention: when a piece moves to the same coordinates as the previous move's piece (as in a capture), the position is simply indicated with 同 (which is pronounced dō or onajiku) instead of the file-rank coordinate numbers. For example, if Black's pawn moved to a square in which White's pawn captured Black's pawn and then both players' bishops recaptured followed by a rook recapture, this could be notated as ☗２四歩 ☖同歩 ☗同角 ☖同角 ☗同飛 which would be equivalent to the western notation sequence 1.P-24 Px24 2.Bx24 Bx24 3.Rx24. 同 always implies a capture (although not all captures will use 同, of course). In some cases where the coordinates may be forgotten by the reader (for instance, if its antecedent is separated by a page turn or several paragraphs of text), then the number coordinates will precede 同 to aid the reader like this: ☖２四同歩. An alternate symbol 仝 is used instead of 同 in older books.[8][9]

It is also possible to encounter Arabic numerals for both the file and rank coordinates, such as ☗２４歩 instead of ☗２四歩.

Also, since Japanese is often written vertically from top to bottom, the notation may be written vertically as well with the top number indicating the file and rank number below the file number. Finally, in older books of the Edo period, the notation may be written from right to left (as is the case with traditional vertical writing) even when the notation is written horizontally. However, this older practice is not used in the modern period, where horizontally writing is read from left to right following European language traditions. (See the 1839 game record image below for such an example.)

Piece[]

Pieces are indicated with kanji (instead of letters as in the western system). The piece's kanji follows the piece's board coordinates. The following symbols are used.

Japanese Western Japanese Western
歩 P と +P
香 L 成香 +L
桂 N 成桂 +N
銀 S 成銀 +S
角 B 馬 +B
飛 R 龍 or 竜 +R
金 G 玉 K

Promoted pieces are indicated with a 成 prefix except for the promoted pawn, promoted bishop, and promoted rook, which are と, 馬, 龍, respectively.

The character for dragon 龍 can also be encountered as its shinjitai form 竜 as well.

兵 is used instead of 歩 in some older texts.[10]

In tsumeshogi, the character 合 is used essentially as a variable that represents a piece of any value. It is used to indicate to an interposing piece (of any kind) that is placed between the king and the opponent's checking piece.

Ambiguity resolution: Movement description[]

When there is ambiguity in piece movement, there is a complex system of movement description using the symbols below. The movement descriptors consist of (a) a dropped piece indicator, (b) movement toward destination indicators, and (c) movement origin indicators.

Movement notation Meaning
打 dropped
引 downward
寄 horizontally
上 upward
右 moving from right (going leftwards)
左 moving from left (going rightwards)
直 perpendicularly vertical (gold/silver only)
行 upward (dragon/horse)
入 upward (dragon/horse)

The symbol for a dropped piece is 打 following the piece's character. In the usual course of a game, most dropped pieces will probably be unambiguous. In these unambiguous cases, explicit notation for the dropped piece is not required and usually omitted (unlike in western notation where the drop notation is obligatory). For example, a western notation such as P*23 will be notated simply as ２三歩 instead of ２三歩打. In other situations, there is a possibility that either a piece that is already in play on the board can move to a certain square or a piece of the same kind that is held in hand can be dropped to that square. In this case, when the piece on the board moves to that square, the notation simply notates the move as usual with no drop indication. However, when the piece in hand is dropped to that location, then the drop indication must be present in the notation in order to resolve the ambiguity. In other words, 打 is only used when the following two conditions are met: (i) a piece is dropped and (ii) there is ambiguity with another piece on the board.

For ambiguity resolution with pieces on the board, the main notation symbols are 引 for downward movement, 寄 for horizontal movement, and 上 for upward movement. Note that these three indicators describe movement toward their destination square.

In the example below, three golds can move to the ７八 square. The gold that originates on ７七 and moves down is notated as ７八金引 (= G77-78). The other two possibilities are notated as ７八金寄 (= G68-78) and ７八金上 (= G79-78).

The 引 and 上 indicate downward and upward movement, respectively, that can be both vertical as well as diagonal.

There are two less common alternate symbols used instead of 上: 行 and 入. However, these alternate symbols are reserved for indicating only the two most powerful promoted dragon 龍 and horse 馬 pieces. Thus, ５五龍行 or ５五龍入 instead of ５五龍上, but not ５五金行 or ５五金入.

In certain situations, an indication of movement toward the destination square (that is, with 引, 寄, 上) is not sufficient to resolve ambiguity. In these cases, the origin square of the piece is notated with a relative positional indicator. These are 右 for a piece moving from the right (and thus moving leftward) and 左 for a piece moving from the left (rightward).

This positional information is relative to each player's directions. Thus, △５二金右 (literally: "white 5-2 gold right") refers to the silver on the right from White's perspective (which would be on the left from Black's perspective).

In the special case of golds and silvers as well as promoted pieces with gold-like movements (成銀, 成桂, 成香, と), it is possible for there to be a three-way ambiguity in upward movement. In this case, a third positional origin indicator is used: 直 for vertical (straight up) movement.

Additionally, this 直 indicator tends to always be used for vertical movement even when simply using 右 ("right") and 左 ("left") would suffice. Relatedly, 直 tends to be used only for golds and silvers and not for other pieces.

Promotion[]

A piece that promotes is indicated with 成 following the piece's character, such as ７三桂成 (N-73+). If a piece does not promote, this is indicated with 不成 following the piece's character, such as ７三桂不成 (N-73=).

There is an alternate symbol for non-promotion: 生 is sometimes used instead of 不成 – for instance, ７三桂生 instead of ７三桂不成.

Numbering[]

Unlike western notation, numbering Japanese game records is not obligatory. Although players' moves often are not numbered, shogi moves are always counted per player's move. This is commonly seen in checkmate problems where a 3-move (３手) checkmate problem would mean a move sequence of black-white-black. This is unlike western chess which counts each pair of moves as one move. (In western notation for shogi, the move numbering tends to follow western chess notation conventions.)

Game end[]

Shogi games are officially over when a player formally resigns. The resignation is notated as 投了 tōryō. Other possible endings include rare 千日手 draw by repetition, 反則手 illegal move, and the very rare 持将棋 draw by impasse.

Other conventions[]

Unlike western notation, a capture of a piece is never explicitly notated in the Japanese system since the capture can be understood in the context of the game. However, when 同 is used, it always implies a capture. So, in this sense 同 is a notated capture. But, other captures of pieces that do not have the same coordinates as the preceding move are simply not indicated in the notation system.

Shorthand[]
A game record from an 1839 Right handicap game between Kenko Ishimoto (石本検校) who is Black (shitate) and Ryusetsu Ohashi (大橋柳雪) who is White. The game record uses shorthand notation. For example, the first move indicated is 七六丶 with the numerals read from right-to-left. This would be written in the standard notation as ７六歩. However, typically, White is notated as the top player these days, so this would be notated more typically as △３四歩 with the western equivalent as 1. ...P-34.

In addition to the usual kanji symbols, there are also shorthand versions of piece symbols that can be written very quickly.[11][12] For several of the symbols, there is variation in what shorthand symbol is used – the ones listed here may not be exhaustive of all the alternatives used in Japan.

Regular symbol Shorthand
歩 丶, フ, ゝ, ・
と と
香 禾, キ, ↑
桂 土
銀 ヨ
金 人
角 ク
馬 マ, ウ
飛 ヒ, 乙
龍 立, リ
玉 王, 玉, ○
成 ナ
不成 フナ, 不ナ
同 －,
WIKI