Hi Can someone help me with this? How can I apply a function to a list of variables. something like this listvar=list("Monday","Tuesday","Wednesday") func=function(x){x[which(x<=10)]=NA} lapply(listvar, func) were Monday=[213,56,345,33,34,678,444] Tuesday=[213,56,345,33,34,678,444] ... in my case I have a neverending list of vectors. Thanks!