Hi Russ, On Sun, May 8, 2011 at 12:07 PM, Russ Abbott <russ.abb...@gmail.com> wrote: > I'm having troubles with the names of columns. > > quantmod deal with stock quotes. I've created an array of the first 5 > closing prices from Jan 2007. (Is there a problem that the name is the same > as the variable name? There shouldn't be.) > >> close > > close > > 2007-01-03 1416.60 > > 2007-01-04 1418.34 > > 2007-01-05 1409.71 > > 2007-01-08 1412.84 > > 2007-01-09 1412.11
It would be appreciated in the future if you provided the object via dput() or some such that is easy to paste in. > > > When I try to create a more complex array by adding columns, the names get > fouled up. Here's a simple example. > >> cbind(changed.close = close+1, zero = 0, close) > > close zero close.1 > > 2007-01-03 1417.60 0 1416.60 > > 2007-01-04 1419.34 0 1418.34 > > 2007-01-05 1410.71 0 1409.71 > > 2007-01-08 1413.84 0 1412.84 > > 2007-01-09 1413.11 0 1412.11 > > > The first column should be called "changed.close", but it's called "close". > The second column has the right name. The third column should be called > "close" but it's called "close.1". Why is that? Am I missing something? Yes. mat <- matrix(1:10, dimnames = list(NULL, "A")) cbind(X = 11:20, Y = mat + 1) cbind(X = 11:20, Y = mat[, "A"] + 1) In particular note that: class(mat) class(mat[, "A"]) It is silly to expect to be able to pass a single name for an entire matrix, while it makes complete sense that that would work for a vector. The problem with naming the column the same thing as the object containing it, is our limited human minds get ramfeezled (R does just fine, as you can see). > > If I change the order of the columns and let close have its original name, > there is still a problem. > >> cbind(close, zero = 0, changed.close = close+1) > > close zero close.1 > > 2007-01-03 1416.60 0 1417.60 > > 2007-01-04 1418.34 0 1419.34 > > 2007-01-05 1409.71 0 1410.71 > > 2007-01-08 1412.84 0 1413.84 > > 2007-01-09 1412.11 0 1413.11 > > > Now the names on the first two columns are ok, but the third column is still > wrong. Again, why is that? Apparently it's not letting me assign a name to > a column that comes from something that already has a name. Is that the way > it should be? > > I don't get that same problem on a simpler example. > >> IX <- cbind(I=0, X=(1:3)) > > > IX > > I X > > [1,] 0 1 > > [2,] 0 2 > > [3,] 0 3 > >> cbind(Y = 1, Z = IX[, "I"], W = IX[, "X"]) > > Y Z W > > [1,] 1 0 1 > > [2,] 1 0 2 > > [3,] 1 0 3 > > > Is this a peculiarity to xts objects? Nope, but do check the type of object you are working with---there are often different methods for different objects so I would not assumet that all things would work the same. Cheers, Josh > > Thanks. > > *-- Russ * > * > * > P.S. Once again I feel frustrated because it's taken me far more time than > it deserves to track down and characterize this problem. I can fix it by > using the names function. But I shouldn't have to do that. > > [[alternative HTML version deleted]] Please post using plain text. > > ______________________________________________ > 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 University of California, Los Angeles http://www.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.
