?file.exists On 4/1/08, CHIB CO <[EMAIL PROTECTED]> wrote: > Hi Jim, > > I just wanted to know if there is a function in R that can tell you whether > a file on the internet exists before you attempt to download it or whether > there is a way of handling the error you get in the download.file() function > without having it break a for loop with the download error when it is part > of that loop. > > Kind Regards > > Chib > > > ________________________________ > > > Date: Mon, 31 Mar 2008 18:33:35 -0500 > > From: [EMAIL PROTECTED] > > To: [EMAIL PROTECTED] > > Subject: Re: [R] download.file error > > CC: r-help@r-project.org > > > > > ?try > > > > On Mon, Mar 31, 2008 at 6:26 PM, CHIB CO <[EMAIL PROTECTED]> wrote: > > > Dear all, > > > > > > I am looking for a way to work out if a file on the internet exists > before attempting to download it using the function download.file(). For > example, > > > using a url that does not exist > > > > > > url <- "http://finance.yahoo.com/ftse.csv"; > > > destfile <- tempfile() > > > download.file(url = url, destfile = destfile) > > > > > > # gives the following response ... > > > > > > trying URL 'http://finance.yahoo.com/ftse.csv' > > > Error in download.file(url = url, destfile = destfile) : > > > cannot open URL 'http://finance.yahoo.com/ftse.csv' > > > In addition: Warning message: > > > In download.file(url = url, destfile = destfile) : > > > cannot open: HTTP status was '404 Not Found' > > > > > > When I am using the download.file() function in a loop over multiple > URLs, the above error will cause the loop to terminate, so I want to avoid > this by checking if the file exists first then wrapping the subsequent > functions in an if() statment. The original fault came from the function > get.hist.quote() in the "tseries" package. I was trying to iterate over > various stocks, but some stocks listed in the yahoo website do not have any > downloadable data associated with them, which causes the loop to terminate. > The "workhorse" function of get.hist.quote() is the download.file() > function. > > > > > > Kind Regards > > > > > > Chib > > > > > > > _________________________________________________________________ > > > Win 100's of Virgin Experience days with BigSnapSearch.com > > > > > > [[alternative HTML version deleted]] > > > > > > > > > ______________________________________________ > > > R-help@r-project.org mailing list > > > https://stat.ethz.ch/mailman/listinfo/r-help > > > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > > > and provide commented, minimal, self-contained, reproducible code. > > > > > > > > > > > > > > -- > > Jim Holtman > > Cincinnati, OH > > +1 513 646 9390 > > > > What is the problem you are trying to solve? > > > ________________________________ > Have you played Fishticuffs? Get fish-slapping on Messenger
-- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem you are trying to solve? ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
