Clean up world development indicator data for analysis (esp in Stata)

gistfile1.r

prep.wdi <- function(x,cache=FALSE,filename=paste(Sys.time()),country='name',format='wide'){
	require(reshape2)
	if (!is.character(x)) {stop('x must be a string.')}
	df <- read.csv(x)
	if (names(df)[1] != 'Country.Name' | 
			names(df)[2] != 'Country.Code' | 
			names(df)[3] != 'Indicator.Name' | 
			names(df)[4] != 'Indicator.Code') {
				stop('This is not a properly formatted WDI csv.')
	}
	if (country != 'name' & country != 'code') {
		stop('Undefined country option. Must be name, code, or both.')
	}
	if (format != 'wide' & format != 'long') {
		stop('Undefined format option. Must be wide or long.')
	}
	if (format == 'wide') {
		if (country == 'name') {
			df <- df[,c(1,3,5:ncol(df))]
			df <- melt(df,id.vars=c('Country.Name','Indicator.Name'))
			names(df)[3] <- "year"
			df$year <- substr(df$year,2,5)
			df <- dcast(df,Country.Name + year ~ Indicator.Name)
		}
		if (country == 'code') {
			df <- df[,c(2,3,5:ncol(df))]
			df <- melt(df,id.vars=c('Country.Code','Indicator.Name'))
			names(df)[3] <- "year"
			df$year <- substr(df$year,2,5)
			df <- dcast(df,Country.Code + year ~ Indicator.Name)
		}
		if (country == 'both') {
			df <- df[,c(1:3,5:ncol(df))]
			df <- melt(df,id.vars=c('Country.Name','Country.Code','Indicator.Name'))
			names(df)[4] <- "year"
			df$year <- substr(df$year,2,5)
			df <- dcast(df,Country.Name + Country.Code + year ~ Indicator.Name)
		}
	}
	if (format == 'long') {
		if (country == 'name') {
			df <- df[,c(1,3,5:ncol(df))]
			df <- melt(df,id.vars=c('Country.Name','Indicator.Name'))
			names(df)[3] <- "year"
			df$year <- substr(df$year,2,5)
		}
		if (country == 'code') {
			df <- df[,c(2,3,5:ncol(df))]
			df <- melt(df,id.vars=c('Country.Code','Indicator.Name'))
			names(df)[3] <- "year"
			df$year <- substr(df$year,2,5)
		}
		if (country == 'both') {
			df <- df[,c(1:3,5:ncol(df))]
			df <- melt(df,id.vars=c('Country.Name','Country.Code','Indicator.Name'))
			names(df)[4] <- "year"
			df$year <- substr(df$year,2,5)
		}
	}
	if (cache == TRUE) {
		write.csv(df, file=paste(filename,'csv',sep='.'), row.names=FALSE)
	}
	return(df)
}