NHL PBP for Tableau.R

###############################################################################
# Date: Feb 13, 2011
# Author: @BrockTibert
# Filename: NHL PBP and Tableau.R
# R version: 2.12.1
# 
# Purpose: Grab the Play by Play event data and visualize live using Tableau
#
#
# Copyright (c) 2011, under the Simplified BSD License.  
# For more information on FreeBSD see: http://www.opensource.org/licenses/bsd-license.php
# All rights reserved. 
###############################################################################


# www.tableausoftware.com/support/knowledge-base/background-image-coordinates

#------------------------------------------------------------------------------
# Setup
#------------------------------------------------------------------------------

## set working directory
DIR <- "C:\\Users\\Brock\\Documents\\My Dropbox\\Eclipse\\Projects\\R\\NHL\\Blog Posts\\PBP and Tableau Mapping"
setwd(DIR)

## open the following libraries
library(XML)
library(RCurl)
library(twitteR)
library(stringr)
library(plyr)



##  function to grab the PBP and parse to list
grab.pbp <- function(GAMEID="2010020677") {
	
	#Takes 1 arguments: GAMEID =  the scraped game id for the 1011 season
	# returns the JSON dataset
	
	URL <- paste("http://live.nhl.com/GameData/20102011/",
			GAMEID, "/PlayByPlay.json", sep="")
	out <- getURL(URL)
	out <- toJSON(out)
	out <- fromJSON(URL)$data$game$plays$play
	
	return(out)
}

## function to parse the data list into a dataframe
parse.pbp <- function(pbp.JSON) {
	
	for(i in 1:length(pbp.JSON)) {
		
		z <- pbp.JSON[[i]]	
		
		# parse the data into a data frame
		df.temp <- as.data.frame(t(unlist(z)), stringsAsFactors=F)	
		df.temp$seqnum <- i
		
		# append the data
		df <- rbind.fill(df, df.temp)
		
	}
	
	return(df)
	
}


## Let's grab the data
pbp <- data.frame()
for (game in c("2010020842")) {
	
	# execue the fuctions
	temp <- try(grab.pbp(GAMEID=game))
	
	if (length(temp) > 0) {
		
		print(paste("# of rows: ", length(temp), sep=""))
		temp.df <- parse.pbp(temp)
		temp.df$gameid <- game
		print("inserting rows")
		pbp <- rbind.fill(pbp, temp.df)
		
	}
	
	rm(temp, temp.df)
	
}


# save the data
write.table(pbp, "Play by Play.csv", sep=",", row.names=F)