[R] Downloading file with lapply

Santosh Srinivas santosh.srinivas at gmail.com
Fri Oct 15 09:19:15 CEST 2010


I'm still getting familiar with lapply

I have this date sequence
x <- seq(as.Date("01-Jan-2010",format="%d-%b-%Y"), Sys.Date(), by=1) #to
generate series of dates

I want to apply the function for all values of x . so I use lapply (Still a
newbie!)
I wrote this test function
pFun <- function (x) {
  print(paste("This is: ",x,sep=""))
  }


When I run it:
> lapply(x,pFun(x))
It gives the result correctly.. but end with an error

 Error in match.fun(FUN) : 
  'pFun(x)' is not a function, character or symbol

Question 1: What is the issue here??


Now, to the real problem. I wrote a function to cmDownFun(sDate)which is
working correctly
If I do cmDownFun (x[6]) .. it works correctly .. (i.e. my function was ok
this time around!)

Hoewever if I do, lapply (x,cmDownFun(x))
It fails at 01-Jan-2010 .... this is because of: HTTP status was '404 Not
Found'

This is OK, because the file does not exist ... but I want to continue for
the remaining values of x
lapply(x,try(cmDownFun(x),silent = TRUE)) .. does not work
I also put the try inside the function itself but does not work either.



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Thanks R-Helpers. Yes, this is a silly question and it will not be repeated!
:-)



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