1. I have a list of lm (linear model) objects. Is it possible to select, through subscripts, a particular element (say, the intercept) from all the models? I've tried something like this: List[[1:length(list)]][1] All members of the list are similar. My goal is to have a list of the intercepts and lists of other estimated parameters. Is it better to convert to a matrix? How to do this? 2. Connected to this, how do I convert from a list back to a vector? This problem arose from using "split" to split a vector by a factor, then selecting a subset of this (ie. length>10), leaving me with subset list of my original. Unsplit(newList, factor) doesn't work, presumably due to my removal of some values. Thoughts? Thanks! -Allen -- View this message in context: http://www.nabble.com/Two-Noobie-questions-tp21316554p21316554.html Sent from the R help mailing list archive at Nabble.com.
On Jan 6, 2009, at 1:50 PM, AllenL wrote:> > 1. I have a list of lm (linear model) objects. Is it possible to > select, > through subscripts, a particular element (say, the intercept) from > all the > models? I've tried something like this:?coef if your list of models is ml, then perhaps something like this partially tested idea: lapply(ml, function(x) coef(x)[1] ) This is what I get using that formulation an available logistic model: > coef(lr.TC_HDL_BMI)[1] Intercept -6.132448> > > List[[1:length(list)]][1] > All members of the list are similar. My goal is to have a list of the > intercepts and lists of other estimated parameters. Is it better to > convert > to a matrix? How to do this? > > 2. Connected to this, how do I convert from a list back to a vector? > This > problem arose from using "split" to split a vector by a factor, then > selecting a subset of this (ie. length>10), leaving me with subset > list of > my original. Unsplit(newList, factor) doesn't work, presumably due > to my > removal of some values. Thoughts??unlist > ll <- list(1,2,3,4) > ll [[1]] [1] 1 [[2]] [1] 2 [[3]] [1] 3 [[4]] [1] 4 > unlist(ll) [1] 1 2 3 4 > str(unlist(ll)) num [1:4] 1 2 3 4 > is.vector(unlist(ll)) [1] TRUE -- David Winsemius> > > Thanks! > -Allen > > > > -- > View this message in context: http://www.nabble.com/Two-Noobie-questions-tp21316554p21316554.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > 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.
Hello, You are not very precise there. Do you mean that the rows in your text file do not all have the same number of separators (commas, in your case)? Best regards, Carlos J. Gil Bellosta http://www.datanalytics.com On Thu, 2009-01-08 at 04:38 -0500, Rahul-A.Agarwal at ubs.com wrote:> I have a data frame with unequal rows length separated by comma.....I > have to read the data first and then calculate number of comma in each > row...how can I do that > > Regards Rahul > > ______________________________________________ > 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.
I doubt that you have a dataframe with those features, since R would not allow such an event; more likely you have data in a file. If your goal is to determine the number of items, then you should definitely look at: ?count.fields count.fields(filename, sep=",") # would give you 1 + the number commas in each line of the file -- David Winsemius On Jan 8, 2009, at 4:38 AM, <Rahul-A.Agarwal at ubs.com> <Rahul-A.Agarwal at ubs.com > wrote:> I have a data frame with unequal rows length separated by comma.....I > have to read the data first and then calculate number of comma in each > row...how can I do that > > Regards Rahul > > ______________________________________________ > 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.