Hi You already got answer from Avi. I often use dim(data) to inspect how many rows/columns I have. After that I check if some columns contain all or many NA values.
colSums(is.na(data)) keep <- which(colSums(is.na(data))<nnn) cleaned.data <- data[, keep] Cheers Petr > -----Original Message----- > From: R-help <r-help-boun...@r-project.org> On Behalf Of Luigi Marongiu > Sent: Friday, August 6, 2021 7:34 AM > To: Duncan Murdoch <murdoch.dun...@gmail.com> > Cc: r-help <r-help@r-project.org> > Subject: Re: [R] Sanity check in loading large dataframe > > Ok, so nothing to worry about. Yet, are there other checks I can implement? > Thank you > > On Thu, 5 Aug 2021, 15:40 Duncan Murdoch, <murdoch.dun...@gmail.com> > wrote: > > > On 05/08/2021 9:16 a.m., Luigi Marongiu wrote: > > > Hello, > > > I am using a large spreadsheet (over 600 variables). > > > I tried `str` to check the dimensions of the spreadsheet and I got > > > ``` >> (str(df)) > 'data.frame': 302 obs. of 626 variables: > > > $ record_id : int 1 1 1 1 1 1 1 1 1 1 ... > > > .... > > > $ v1_medicamento___aceta : int 1 NA NA NA NA NA NA NA NA NA ... > > > [list output truncated] > > > NULL > > > ``` > > > I understand that `[list output truncated]` means that there are > > more > variables than those allowed by str to be displayed as rows. > > Thus I > increased the row's output with: > > > ``` > > > > > >> (str(df, list.len=1000)) > > > 'data.frame': 302 obs. of 626 variables: > > > $ record_id : int 1 1 1 1 1 1 1 1 1 1 ... > > > ... > > > NULL > > > ``` > > > > > > Does `NULL` mean that some of the variables are not closed? > > (perhaps a > missing comma somewhere) > Is there a way to check the > > sanity of the data and avoid that some > separator is not in the > > right place? > > > Thank you > > > > The NULL is the value returned by str(). Normally it is not printed, > > but when you wrap str in parens as (str(df, list.len=1000)), that > > forces the value to print. > > > > str() is unusual in R functions in that it prints to the console as it > > runs and returns nothing. Many other functions construct a value > > which is only displayed if you print it, but something like > > > > x <- str(df, list.len=1000) > > > > will print the same as if there was no assignment, and then assign > > NULL to x. > > > > Duncan Murdoch > > > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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.
______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
