Overview

For this project, I will use R to extract player information from a text file containing chess tournament results. The final dataset will include each player’s name, state, total points, pre-tournament rating, and average pre-tournament rating of their opponents. I will then export the completed dataframe as a CSV file.

Loading the Tournament Data

I loaded the original text file into R as separate lines. I will use the repeated structure of the file to identify the player records and extract the required information.

tournament_lines <- readLines(
  "tournamentinfo.txt",
  warn = FALSE
)

length(tournament_lines)
## [1] 196
head(tournament_lines, 10)
##  [1] "-----------------------------------------------------------------------------------------" 
##  [2] " Pair | Player Name                     |Total|Round|Round|Round|Round|Round|Round|Round| "
##  [3] " Num  | USCF ID / Rtg (Pre->Post)       | Pts |  1  |  2  |  3  |  4  |  5  |  6  |  7  | "
##  [4] "-----------------------------------------------------------------------------------------" 
##  [5] "    1 | GARY HUA                        |6.0  |W  39|W  21|W  18|W  14|W   7|D  12|D   4|" 
##  [6] "   ON | 15445895 / R: 1794   ->1817     |N:2  |W    |B    |W    |B    |W    |B    |W    |" 
##  [7] "-----------------------------------------------------------------------------------------" 
##  [8] "    2 | DAKSHESH DARURI                 |6.0  |W  63|W  58|L   4|W  17|W  16|W  20|W   7|" 
##  [9] "   MI | 14598900 / R: 1553   ->1663     |N:2  |B    |W    |B    |W    |B    |W    |B    |" 
## [10] "-----------------------------------------------------------------------------------------"

Identifying Player Records

Each player’s information appears across two lines. The first line contains the player’s number, name, points, and opponents. The second line contains the player’s state and pre-tournament rating. I identified these two types of lines using their repeated patterns.

player_line_numbers <- grep(
  "^\\s*[0-9]+\\s*\\|",
  tournament_lines
)

rating_line_numbers <- grep(
  "^\\s*[A-Z]{2}\\s*\\|",
  tournament_lines
)

player_lines <- tournament_lines[player_line_numbers]
rating_lines <- tournament_lines[rating_line_numbers]

length(player_lines)
## [1] 64
length(rating_lines)
## [1] 64

Extracting Player Information

I separated each record at the vertical bars in the text file. From these fields, I extracted each player’s tournament number, name, total points, state, and pre-tournament rating.

split_record <- function(record) {
  trimws(strsplit(record, "|", fixed = TRUE)[[1]])
}

player_fields <- lapply(player_lines, split_record)
rating_fields <- lapply(rating_lines, split_record)

pair_number <- as.integer(
  sapply(player_fields, function(record) record[1])
)

player_name <- sapply(
  player_fields,
  function(record) record[2]
)

total_points <- as.numeric(
  sapply(player_fields, function(record) record[3])
)

player_state <- sapply(
  rating_fields,
  function(record) record[1]
)

rating_text <- sapply(
  rating_fields,
  function(record) record[2]
)

pre_rating <- as.integer(
  sub(".*R:\\s*([0-9]+).*", "\\1", rating_text)
)

player_information <- data.frame(
  pair_number,
  player_name,
  player_state,
  total_points,
  pre_rating,
  stringsAsFactors = FALSE
)

head(player_information)
##   pair_number         player_name player_state total_points pre_rating
## 1           1            GARY HUA           ON          6.0       1794
## 2           2     DAKSHESH DARURI           MI          6.0       1553
## 3           3        ADITYA BAJAJ           MI          6.0       1384
## 4           4 PATRICK H SCHILLING           MI          5.5       1716
## 5           5          HANSHI ZUO           MI          5.5       1655
## 6           6         HANSEN SONG           OH          5.0       1686

Extracting Opponent Numbers

Each completed round contains a result—win, loss, or draw—followed by the opponent’s player number. Entries such as byes, half-point byes, and unplayed rounds do not identify an opponent, so I excluded them.

round_results <- lapply(
  player_fields,
  function(record) record[4:10]
)

extract_opponents <- function(rounds) {
  
  completed_games <- grepl(
    "^[WLD]\\s*[0-9]+",
    rounds
  )
  
  opponent_ids <- sub(
    "^[WLD]\\s*([0-9]+).*$",
    "\\1",
    rounds[completed_games]
  )
  
  as.integer(opponent_ids)
}

opponent_numbers <- lapply(
  round_results,
  extract_opponents
)

opponent_numbers[[1]]
## [1] 39 21 18 14  7 12  4

Calculating Average Opponent Ratings

I matched each opponent number with that opponent’s pre-tournament rating. I then calculated the mean of those ratings for every player and rounded the result to the nearest whole number, following the assignment example.

average_opponent_pre_rating <- sapply(
  opponent_numbers,
  function(opponent_ids) {
    
    opponent_ratings <- pre_rating[
      match(opponent_ids, pair_number)
    ]
    
    round(mean(opponent_ratings))
  }
)

chess_results <- data.frame(
  player_name,
  player_state,
  total_points,
  pre_rating,
  average_opponent_pre_rating,
  stringsAsFactors = FALSE
)

head(chess_results)
##           player_name player_state total_points pre_rating
## 1            GARY HUA           ON          6.0       1794
## 2     DAKSHESH DARURI           MI          6.0       1553
## 3        ADITYA BAJAJ           MI          6.0       1384
## 4 PATRICK H SCHILLING           MI          5.5       1716
## 5          HANSHI ZUO           MI          5.5       1655
## 6         HANSEN SONG           OH          5.0       1686
##   average_opponent_pre_rating
## 1                        1605
## 2                        1469
## 3                        1564
## 4                        1574
## 5                        1501
## 6                        1519

Final Tournament Results

The final dataframe contains the five required fields for all 64 players. I checked the number of rows and searched for missing values before exporting the results.

nrow(chess_results)
## [1] 64
colSums(is.na(chess_results))
##                 player_name                player_state 
##                           0                           0 
##                total_points                  pre_rating 
##                           0                           0 
## average_opponent_pre_rating 
##                           0
knitr::kable(
  chess_results,
  caption = "Chess Tournament Player Results"
)
Chess Tournament Player Results
player_name player_state total_points pre_rating average_opponent_pre_rating
GARY HUA ON 6.0 1794 1605
DAKSHESH DARURI MI 6.0 1553 1469
ADITYA BAJAJ MI 6.0 1384 1564
PATRICK H SCHILLING MI 5.5 1716 1574
HANSHI ZUO MI 5.5 1655 1501
HANSEN SONG OH 5.0 1686 1519
GARY DEE SWATHELL MI 5.0 1649 1372
EZEKIEL HOUGHTON MI 5.0 1641 1468
STEFANO LEE ON 5.0 1411 1523
ANVIT RAO MI 5.0 1365 1554
CAMERON WILLIAM MC LEMAN MI 4.5 1712 1468
KENNETH J TACK MI 4.5 1663 1506
TORRANCE HENRY JR MI 4.5 1666 1498
BRADLEY SHAW MI 4.5 1610 1515
ZACHARY JAMES HOUGHTON MI 4.5 1220 1484
MIKE NIKITIN MI 4.0 1604 1386
RONALD GRZEGORCZYK MI 4.0 1629 1499
DAVID SUNDEEN MI 4.0 1600 1480
DIPANKAR ROY MI 4.0 1564 1426
JASON ZHENG MI 4.0 1595 1411
DINH DANG BUI ON 4.0 1563 1470
EUGENE L MCCLURE MI 4.0 1555 1300
ALAN BUI ON 4.0 1363 1214
MICHAEL R ALDRICH MI 4.0 1229 1357
LOREN SCHWIEBERT MI 3.5 1745 1363
MAX ZHU ON 3.5 1579 1507
GAURAV GIDWANI MI 3.5 1552 1222
SOFIA ADINA STANESCU-BELLU MI 3.5 1507 1522
CHIEDOZIE OKORIE MI 3.5 1602 1314
GEORGE AVERY JONES ON 3.5 1522 1144
RISHI SHETTY MI 3.5 1494 1260
JOSHUA PHILIP MATHEWS ON 3.5 1441 1379
JADE GE MI 3.5 1449 1277
MICHAEL JEFFERY THOMAS MI 3.5 1399 1375
JOSHUA DAVID LEE MI 3.5 1438 1150
SIDDHARTH JHA MI 3.5 1355 1388
AMIYATOSH PWNANANDAM MI 3.5 980 1385
BRIAN LIU MI 3.0 1423 1539
JOEL R HENDON MI 3.0 1436 1430
FOREST ZHANG MI 3.0 1348 1391
KYLE WILLIAM MURPHY MI 3.0 1403 1248
JARED GE MI 3.0 1332 1150
ROBERT GLEN VASEY MI 3.0 1283 1107
JUSTIN D SCHILLING MI 3.0 1199 1327
DEREK YAN MI 3.0 1242 1152
JACOB ALEXANDER LAVALLEY MI 3.0 377 1358
ERIC WRIGHT MI 2.5 1362 1392
DANIEL KHAIN MI 2.5 1382 1356
MICHAEL J MARTIN MI 2.5 1291 1286
SHIVAM JHA MI 2.5 1056 1296
TEJAS AYYAGARI MI 2.5 1011 1356
ETHAN GUO MI 2.5 935 1495
JOSE C YBARRA MI 2.0 1393 1345
LARRY HODGE MI 2.0 1270 1206
ALEX KONG MI 2.0 1186 1406
MARISA RICCI MI 2.0 1153 1414
MICHAEL LU MI 2.0 1092 1363
VIRAJ MOHILE MI 2.0 917 1391
SEAN M MC CORMICK MI 2.0 853 1319
JULIA SHEN MI 1.5 967 1330
JEZZEL FARKAS ON 1.5 955 1327
ASHWIN BALAJI MI 1.0 1530 1186
THOMAS JOSEPH HOSMER MI 1.0 1175 1350
BEN LI MI 1.0 1163 1263

Exporting the CSV File

I exported the completed dataframe as a CSV file so it can be used in another program or imported into a database.

write.csv(
  chess_results,
  "chess_tournament_results.csv",
  row.names = FALSE
)

file.exists("chess_tournament_results.csv")
## [1] TRUE

Conclusion

I successfully extracted the required information for all 64 chess players from the original tournament text file. I used each player’s round results to identify their opponents and matched those opponent numbers with their pre-tournament ratings. The final dataframe contains each player’s name, state, total points, pre-rating, and average opponent pre-rating. I also exported the completed results as a CSV file that can be imported into a database or used for further analysis.

Generative AI Use

I used ChatGPT to help develop parts of the R code, understand how to extract information from the structured text file, and check the final calculations.

OpenAI. (2026). ChatGPT (GPT-5) [Large language model]. https://chatgpt.com. Accessed September 26, 2026.