Hi R community, i created a function (mkdate) as follows: mkdate = function(x) { x$date = as.Date(paste(x$year, x$month, x$day, sep="-")) x$wy = ifelse(x$month >=10, x$year+1, x$year) x$yd = as.integer(format(as.Date(x$date), format="%j")) x$wyd = cal.wyd(x) x } the function results in adding the new columns date, wy, yd, and wyd to the table i apply it to. this has always worked in R version 2.14.2. however, in R version 3.1.0 - instead of my mkdate function adding those columns to my existing table, it just overwrites my table and leaves me with just a list of the last variable created by my mkdate function. so i end up with just a list of numbers representing wyd, and lose all the data in my original table. does anyone know what would now be causing this to occur, and what i need to do to make my function work properly again? thank you for any assistance, Janet [[alternative HTML version deleted]]