Yes, that means to control decimal numbers. For example, use round(2.3122, digits=1), it gets 2.3
On Tue, May 9, 2017 at 9:11 AM, Doran, Harold <hdo...@air.org> wrote: > ?round > > > > > > *From:* lily li [mailto:chocol...@gmail.com] > *Sent:* Tuesday, May 09, 2017 11:10 AM > *To:* Charles Determan <cdeterma...@gmail.com> > *Cc:* Doran, Harold <hdo...@air.org>; R mailing list <r-help@r-project.org > > > *Subject:* Re: [R] About calculating average values from several matrices > > > > Thanks very much, it works. But how to round the values to have only 1 > decimal digit or 2 decimal digits? I think by dividing, the values are > double type now. Thanks again. > > > > > > On Tue, May 9, 2017 at 9:04 AM, Charles Determan <cdeterma...@gmail.com> > wrote: > > If you want the mean of each element across you list of matrices the > following should provide what you are looking for where Reduce sums all > your matrix elements across matrices and the simply divided my the number > of matrices for the element-wise mean. > > Reduce(`+`, mylist)/length(mylist) > > Regards, > > Charles > > > > On Tue, May 9, 2017 at 9:52 AM, lily li <chocol...@gmail.com> wrote: > > I meant for each cell, it takes the average from other dataframes at the > same cell. I don't know how to deal with row names and col names though, so > it has the error message. > > On Tue, May 9, 2017 at 8:50 AM, Doran, Harold <hdo...@air.org> wrote: > > > It’s not clear to me what your actual structure is. Can you provide > > str(object)? Assuming it is a list, and you want the mean over all cells > or > > columns, you might want like this: > > > > > > > > myData <- vector("list", 3) > > > > > > > > for(i in 1:3){ > > > > myData[[i]] <- matrix(rnorm(100), 10, 10) > > > > } > > > > > > > > ### mean over all cells > > > > sapply(myData, function(x) mean(x)) > > > > > > > > ### mean over all columns > > > > sapply(myData, function(x) colMeans(x)) > > > > > > > > > > > > > > > > > > > > > > > > *From:* lily li [mailto:chocol...@gmail.com] > > *Sent:* Tuesday, May 09, 2017 10:44 AM > > *To:* Doran, Harold <hdo...@air.org> > > *Cc:* R mailing list <r-help@r-project.org> > > *Subject:* Re: [R] About calculating average values from several matrices > > > > > > > > > > I'm trying to get a new dataframe or whatever to call, which has the same > > structure with each file as listed above. For each cell in the new > > dataframe or the new file, it is the average value from former dataframes > > at the same location. Thanks. > > > > > > > > On Tue, May 9, 2017 at 8:41 AM, Doran, Harold <hdo...@air.org> wrote: > > > > Are you trying to take the mean over all cells, or over rows/columns > > within each dataframe. Also, are these different dataframes stored > within a > > list or are they standalone? > > > > > > > > > > -----Original Message----- > > From: R-help [mailto:r-help-boun...@r-project.org] On Behalf Of lily li > > Sent: Tuesday, May 09, 2017 10:39 AM > > To: R mailing list <r-help@r-project.org> > > > Subject: [R] About calculating average values from several matrices > > > > Hi R users, > > > > I have a question about manipulating the data. > > For example, there are several such data frames or matrices, and I want > to > > calculate the average value from all the data frames or matrices. How to > do > > it? Also, should I convert them to data frame or matrix first? Right now, > > when I use typeof() function, each one is a list. > > > > file1 > > jan feb mar apr may jun jul aug sep oct > nov > > > > app1 1.1 1.2 0.8 0.9 1.3 1.5 2.2 3.2 3.0 1.2 > 1.1 > > app2 3.1 3.2 2.8 2.5 2.3 2.5 3.2 3.0 2.9 1.8 > 1.8 > > app3 5.1 5.2 3.8 4.9 5.3 5.5 5.2 4.2 5.0 4.2 > 4.1 > > > > file2 > > jan feb mar apr may jun jul aug sep oct > nov > > > > app1 1.9 1.5 0.5 0.9 1.2 1.8 2.5 3.7 3.2 1.5 > 1.6 > > app2 3.5 3.7 2.3 2.2 2.5 2.0 3.6 3.2 2.8 1.2 > 1.4 > > app3 5.5 5.0 3.5 4.4 5.4 5.6 5.3 4.4 5.2 4.3 > 4.2 > > > > file3 has the similar structure and values... > > > > There are eight such files, and when I use the function mean(file1, > file2, > > file3, ..., file8), it returns the error below. Thanks for your help. > > > > Warning message: > > In mean.default(file1, file2, file3, file4, file5, file6, file7, : > > argument is not numeric or logical: returning NA > > > > [[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. > > > > > > > > [[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. > > > > > [[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.