On 1/1/2007 11:22 AM, Feng Qiu wrote: > Hi Duncan: > Thanks for your hints. > I'm trying to collect distinct elements in one column in a matrix. > If there is a map, I can easily build up such a collection. While if using > list, I have to check by myself if this element already exists in the > collection every time I examine a new entry in the column.
You might want to use the unique() function, or duplicated(), rather than doing this yourself. Duncan Murdoch > > Best, > > Feng > > ----- Original Message ----- > From: "Duncan Murdoch" <[EMAIL PROTECTED]> > To: "Feng Qiu" <[EMAIL PROTECTED]> > Cc: <r-help@stat.math.ethz.ch> > Sent: Monday, January 01, 2007 10:37 AM > Subject: Re: [R] Any container in R? > > >> On 1/1/2007 10:17 AM, Feng Qiu wrote: >>> R has list and array to contain elements. But does R have more powerful >>> container, such as "map" as in C++ STL? or is there such a package? >> In what way are maps more powerful than lists? You can use names to index >> lists. >> >> The other container in R is the environment; they have fairly strange >> semantics, though. >> >> 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.
