On Wed, Feb 3, 2010 at 1:47 PM, Bert Gunter <[email protected]> wrote: > -- and you didn't read my reply.
I did. You said to use a loop. I think flatten a tree to a certain level shouldn't be done with a loop. Loop is a way used in the imperative programming style. Flatten is in the functional programming style. I don't think that it is a good idea to mix the two. Also, the flatten a tree to a certain level operation should be extracted to a well defined function for re-usability. Using a loop is a bad idea to enhance re-usability. > > -----Original Message----- > From: [email protected] [mailto:[email protected]] On > Behalf Of Peng Yu > Sent: Wednesday, February 03, 2010 11:40 AM > To: [email protected] > Subject: Re: [R] How to flatten a tree (based on list) to a certain depth? > > On Wed, Feb 3, 2010 at 12:26 PM, Bert Gunter <[email protected]> wrote: >> RTFM (?unlist -- the "recursive" parameter) >> and do it with a loop however many times you like. > > How do you know that I didn't read the manual? I didn't quite get my > question. Please see my response to Steve. > >> -----Original Message----- >> From: [email protected] [mailto:[email protected]] > On >> Behalf Of Peng Yu >> Sent: Wednesday, February 03, 2010 10:20 AM >> To: [email protected] >> Subject: [R] How to flatten a tree (based on list) to a certain depth? >> >> Suppose that I have the following list of lists of frames 'root' >> (let's call it a 'tree' of frames). I want to flatten it to be a list >> of frames. However, if I unlist(root), it will flatten the frames as >> well. Is there a simply way to flatten the tree to certain depth? >> >> aframe1=data.frame(x=1:3,y=1:3) >> aframe2=data.frame(u=7:9,v=11:13) >> aframe3=data.frame(p=3:5,q=6:8) >> >> main1=list(sub1=aframe1, sub2=aframe2) >> main2=list(sub3=aframe3) >> >> root=list(main1=main1, main2=main2) >> >> str(root) >> unlist(root) >> >> ______________________________________________ >> [email protected] 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. >> >> > > ______________________________________________ > [email protected] 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. > > ______________________________________________ [email protected] 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.
