Hi Thomas, This is non trivial to do, but if you will be working with this sort of data and are inclined to do some programming, you might consider creating a new class. S4 classes and methods are quite flexible, and you can allow them to lean on or inherit from existing classes such as matrices. For example, your class might consist of three lists and a data frame. The length of each list would be forced to be equal to the number of rows in the data frame. Each element of each list would support a length 2 numeric vector (or integer vector or whatever it is you need). THe lists then would hold nodes 1 - 3, and the data frame would hold other information. You can similarly write methods so that for your special class,
d[1, 1] would return c(x1, y1), essentially you create a mix of lists and a matrix with all the necessary constraints, and you develop methods that allow you to operate on this in a way that is sensible for your data. This is stab in the dark, but if you happen to be dealing with social network style data, (triangles and neighbors make me think of that), you should investigate existing packages for that as they may already have their own classes/have a way they expect data to be structured. Off the top of my head, the package "sna" comes to mind as a starting place to look (though I am not personally very familiar with it). Cheers, Josh On Thu, Jul 5, 2012 at 9:37 AM, Thomas C. <thomas.csa...@gmail.com> wrote: > well thank you, i think we get closer to my problem. but i meant it in a > different way. maybe i describe what i intended to do: > > i have number of triangles which i'd like to store in a list, matrix,...etc. > i thought it could look sth. like that: > > triangle node1 node2 node3 ..... > 1 c(x1,y1) c(x2,y3) c(x3,y3) > 1 c(x4,y4) c(x5,y5) c(x6,y6) > . > . > . > > i know that i could just make more rows for the x/y values but the problem > is, that i need to store more than these properties (say the neighbours of > these nodes and their coordinates) and i thought it would be more convenient > to save these as vectors. it was just a thought... is this possible? > > > > -- > View this message in context: > http://r.789695.n4.nabble.com/vector-entry-in-matix-tp4635478p4635509.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help@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. -- Joshua Wiley Ph.D. Student, Health Psychology Programmer Analyst II, Statistical Consulting Group University of California, Los Angeles https://joshuawiley.com/ ______________________________________________ R-help@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.