Can someone help to translate the following STATA do.file into R? Thanks!
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cd mydirectory
mkdir temp
forvalues i=1999/2012 {
        import delimited mydata_`i'.csv,clear
        replace xx=subinstr(xx,",","",.)
        replace yy=subinstr(yy,",","",.)
        destring xx yy, replace
        collapse (sum) xx yy, by(year stcntybr regagnt)
        save "temp/mydata`i'",replace
}
use "temp/mydata2012",clear
forvalues i=1999/2011 {
append using "temp/mydata`i'"
}
save "allNeed",replace
erase temp // remove all files
rmdir temp // remove empty folder