Sabatier, Jennifer F. (CDC/OID/NCHHSTP)
2010-May-19 17:36 UTC
[R] Blanking out specific cells in a data frame
Hi R-Help, I am a new R user. I have used SAS for many years (just FYI on what I am used to and possible obstacles it presents). I have a data frame: mydf <-data.frame(matrix(rnorm(102), ncol=6) I would like to be able to delete ALL the information in column 6 for rows 2 through r, where r=#rows. How can I do that? I want the resulting data frame to look like this: X1 X2 X3 X4 X5 X6 Data data data data data data Data data data data data Data data data data data Data data data data data Data data data data data Data data data data data Data data data data data Data data data data data Data data data data data Data data data data data Data data data data data Data data data data data Data data data data data Data data data data data Data data data data data Data data data data data Data data data data data (Sorry for using the word "data" and not having a cut and paste of my actual data frame...the computer I am writing this email on does not have R so I have to improvise.) Thanks, Jen
Am 19.05.2010 19:36, schrieb Sabatier, Jennifer F. (CDC/OID/NCHHSTP):> mydf<-data.frame(matrix(rnorm(102), ncol=6) >you mean something like: mydf[2:length(mydf[,1]),6]<-NA hth Stefan
Hi Jen, You cannot have a dataframe with unequal column lengths, so you have two options (well maybe more, but two that come to mind): set the values to missing instead of deleting them, or store your data in a list instead of a data frame. For option 1 (recommended) all you need is mydf[-1, 6] <- NA Best, Ista On Wednesday 19 May 2010 1:36:50 pm Sabatier, Jennifer F. (CDC/OID/NCHHSTP) wrote:> Hi R-Help, > > I am a new R user. I have used SAS for many years (just FYI on what I > am used to and possible obstacles it presents). > > I have a data frame: > > mydf <-data.frame(matrix(rnorm(102), ncol=6) > > I would like to be able to delete ALL the information in column 6 for > rows 2 through r, where r=#rows. > > How can I do that? > > I want the resulting data frame to look like this: > > X1 X2 X3 X4 X5 X6 > Data data data data data data > Data data data data data > Data data data data data > Data data data data data > Data data data data data > Data data data data data > Data data data data data > Data data data data data > Data data data data data > Data data data data data > Data data data data data > Data data data data data > Data data data data data > Data data data data data > Data data data data data > Data data data data data > Data data data data data > > > (Sorry for using the word "data" and not having a cut and paste of my > actual data frame...the computer I am writing this email on does not > have R so I have to improvise.) > > Thanks, > > Jen > > ______________________________________________ > R-help at 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.