Re: [R] Setting up a blank table with column names in the hard drive
On 23/06/2007 7:51 PM, Yuchen Luo wrote: > Dear Professor Murdoch. > Thank you so much! Your help is highly appreciated! Please send replies to the mailing list. > > When I use the following commands, there is a blank cell before title "name" > in the resulting csv (excel) file. I am wondering how to get rid of it? I > want to get rid of it because when I write subsequent rows to the file, the > "name" part start from the beginning which is not aligned with the first > line of the column titles. That's a place holder for the row names. If you don't want it, specify row.names=FALSE (and do the same when you write subsequent lines). Duncan Murdoch > > " blank <- data.frame(name=character(0), wife=character(0), > no.children=numeric(0)) > write.csv(blank, 'file.csv')" > > Thank you for your help again and your time is highly appreciated! > > Best Wishes > Yuchen Luo > I > > > On 6/23/07, Duncan Murdoch <[EMAIL PROTECTED]> wrote: >> Yuchen Luo wrote: >>> Dear Friends. >>> Greetings! >>> >>> This should be a very common operation and I believe there should be a >> nice >>> way in R to handle it. I couldn't find it in the manual or by searching >> on >>> line. I am wondering if I could ask for some help in this community. >>> >>> >>> >>> I am trying to record the results of my program to a csv file in the >> hard >>> drive so as to save memory space and also to read the results in excel >> after >>> running the program. Every loop of my program will result in a list >> with >>> element belonging to different class. For example, things like >>> >>> >>> >>> a1 <- list(name="Fred", wife="Mary", no.children=3) >>> a2 <- list(name="Tom", wife="Joy", no.children=9) >>> a3 <- list(name="Paul", wife="Alic", no.children=5) >>> >>> >>> >>> I want the columns to have titles, in the example above, I want to see >> the >>> title "name", "wife" and "no.children" in the excel file. >>> >>> >>> >>> To set up the table in the csv file, I need to add at least one row in >> the >>> table up front. How ever, I do not have the first loop of the program >>> completed yet at that time. If I add a row that is meaningless, how may >> I >>> delete it after all the loops are completed and all the meaningful rows >> are >>> added to the table? >>> >>> >> I'd use data frames rather than plain lists for the results, so >> write.csv will work. >> >> Create a data frame with 0 rows, and write it out: this will give you >> your header line. >> >> e.g. >> >> >> >> Now you can rbind new lines onto the data frame as you calculate new >> records and rewrite the whole thing, or just append them to the file >> with append=TRUE and writing with col.names=FALSE. >> >> Duncan Murdoch >> >> > __ R-help@stat.math.ethz.ch 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.
Re: [R] Setting up a blank table with column names in the hard drive
Yuchen Luo gmail.com> writes:
> This should be a very common operation and I believe there should be a nice
> way in R to handle it. I couldn't find it in the manual or by searching on
> line. I am wondering if I could ask for some help in this community.
>
> I am trying to record the results of my program to a csv file in the hard
> drive so as to save memory space and also to read the results in excel after
> running the program. Every loop of my program will result in a list with
> element belonging to different class. For example, things like
>
> a1 <- list(name="Fred", wife="Mary", no.children=3)
> a2 <- list(name="Tom", wife="Joy", no.children=9)
> a3 <- list(name="Paul", wife="Alic", no.children=5)
>
> I want the columns to have titles, in the example above, I want to see the
> title "name", "wife" and "no.children" in the excel file.
Use a data frame to do the work, and save it with write.table or write.csv
maxallocate=10 # we assume no more than 10 members
myfamily = data.frame(name=rep(NA,maxallocate),wife=NA,nchildren=NA)
myfamily[1,]=c("Fred","Ginger",3)
myfamily[2,]=c("Charles","Mary",1)
myfamily[4,]=c("Frank","Salsa",4)
myfamily$name[3]="Anton"
myfamily$wife[3]="Sue"
myfamily$name[10] = "Charly"
myfamily$name[8] = "Fuhrman"
myfamily= myfamily[-1,] # delete first row
myfamily= myfamily[-1,] # delete current first row, i.e. Charles
# cleanup: assume that all entries having a name are valid
myfamily = myfamily[!is.na(myfamily$name),]
# oops .. I forgot .. another family member turned up unexpectedly
#Add it explicitely
rbind(myfamily,c("Tango","Tanga",33))
# The easy part. Check write.table for other options
write.csv(myfamily,file="myfamily.csv",row.names=FALSE)
__
R-help@stat.math.ethz.ch 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.
Re: [R] Setting up a blank table with column names in the hard drive
Yuchen Luo wrote: > Dear Friends. > Greetings! > > This should be a very common operation and I believe there should be a nice > way in R to handle it. I couldn't find it in the manual or by searching on > line. I am wondering if I could ask for some help in this community. > > > > I am trying to record the results of my program to a csv file in the hard > drive so as to save memory space and also to read the results in excel after > running the program. Every loop of my program will result in a list with > element belonging to different class. For example, things like > > > > a1 <- list(name="Fred", wife="Mary", no.children=3) > a2 <- list(name="Tom", wife="Joy", no.children=9) > a3 <- list(name="Paul", wife="Alic", no.children=5) > > > > I want the columns to have titles, in the example above, I want to see the > title "name", "wife" and "no.children" in the excel file. > > > > To set up the table in the csv file, I need to add at least one row in the > table up front. How ever, I do not have the first loop of the program > completed yet at that time. If I add a row that is meaningless, how may I > delete it after all the loops are completed and all the meaningful rows are > added to the table? > > I'd use data frames rather than plain lists for the results, so write.csv will work. Create a data frame with 0 rows, and write it out: this will give you your header line. e.g. blank <- data.frame(name=character(0), wife=character(0), no.children=numeric(0)) write.csv(blank, 'file.csv') Now you can rbind new lines onto the data frame as you calculate new records and rewrite the whole thing, or just append them to the file with append=TRUE and writing with col.names=FALSE. Duncan Murdoch __ R-help@stat.math.ethz.ch 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.
