process.games: Given downloaded NHL games, produce event tables with players on ice.

Description

Produces game tables from the NHL source files.

Usage

process.single.game (season="20122013",
                       gcode="20001",
                       rdata.folder="nhlr-data",
                       override.download=FALSE,
                       save.to.file=TRUE)
  process.games       (games=full.game.database(),
                       rdata.folder="nhlr-data",
                       override.download=FALSE)
  retrieve.game       (season="20122013",
                       gcode="20001",
                       rdata.folder="nhlr-data",
                       force=TRUE)
  compile.all.games   (mega.file="nhlscrapr-probs.RData",
                       output.file=mega.file,
                       rdata.folder="nhlr-data",
                       new.game.table=NULL)

Arguments

season

A character string for the two years specifying an NHL season.

gcode

The five-digit ID number for a particular NHL game.

rdata.folder

The location within the current directory to which to save the downloaded files. Will be created if it does not exist.

games, new.game.table

A game database, such as the one produced by full.game.database().

override.download

Re-download the game files whether or not they are currently locally available.

save.to.file

Save the game object to file.

force

If TRUE, reprocesses the single game file.

output.file

The name of a file into which the game event list will be saved.

mega.file

Input file for storing all information.

Value

process.single.game() produces an object called game.info that contains several pieces of information, primarily the data.frame playbyplay, with each column representing an event. Columns are as follows: event: The event number as recorded in the game. period, seconds: The period of the game and the elapsed time in seconds. a1,...,a6: The numbers and names of the away team players on the ice. h1,...,h6: The numbers and names of the home team players on the ice. ev.team: The team that registered the event in question. ev.player.1, ev.player.2, ev.player.3: The players involved in the event. distance: The distance in feet from the relevant goal for a shot on goal, missed shot or goal. type: Further information on the event, either shot type or penalty type. homezone: The zone in which the event took place, from the perspective of the home team. xcoord, ycoord: If available, the (x,y) location of a shot on goal or hit.
process.games() runs this routine and saves all game files to disk.
retrieve.game() retrieves the processed file from disk if it exists, and if not, it runs process.single.game() first.
compile.all.games() does everything that's needed to construct the entire record. This will be fastest if all games have already been downloaded and processed, possibly in parallel.

Details

This group of functions takes the downloaded HTML, image and JSON files and produces an event table for each game, particularly focusing on the players on the ice during each event.