For the last statement we may prefer this so it stays a zoo object: > m <- merge(Az, Bz, fill = 0) > m[,1] - m[,2] 1 2 3 4 5 1429 0 3049 0 2219
On Sat, Jul 26, 2008 at 5:53 PM, Gabor Grothendieck <[EMAIL PROTECTED]> wrote: > Look at merge.zoo > >> library(zoo) >> dput(A) > structure(list(DayOfYear = 1:5, x = c(1429L, 3952L, 3049L, 2844L, > 2219L)), .Names = c("DayOfYear", "x"), class = "data.frame", row.names = > c("1", > "2", "3", "4", "5")) >> B <- A[c(2,4),] >> Az <- zoo(A$x, A$DayOfYear) >> Bz <- zoo(B$x, B$DayOfYear) >> merge(Az, Bz, fill = 0) > Az Bz > 1 1429 0 > 2 3952 3952 > 3 3049 0 > 4 2844 2844 > 5 2219 0 >> merge(Az, Bz, fill = 0) %*% c(1, -1) > [,1] > [1,] 1429 > [2,] 0 > [3,] 3049 > [4,] 0 > [5,] 2219 > > > On Sat, Jul 26, 2008 at 5:26 PM, <[EMAIL PROTECTED]> wrote: >> I have two vectos (list) that represent a years of data. Each "row" is >> represented by the day of year and the quantity that was sold for that day. >> I would like to form a new vector that is the difference between the two >> years of data. A sample of A (and similarly B) looks like: >> >>> A[1:5,] >> DayOfYear x >> 1 1 1429 >> 2 2 3952 >> 3 3 3049 >> 4 4 2844 >> 5 5 2219 >>> >> >> D <- A - B >> >> This works just fine if A and B are both the same length. How is the best >> way to handle the situation where A and B are of different lengths? If the >> day of year exists in both vectors (lists) then I just want the coorespondng >> "row" in D to be the difference btween A and B values. If the "row" doesn't >> exist in either A or B then the difference should be treated as if the >> missing "row" was zero. Is this feasible? >> >> Thank you. >> >> Kevin >> >> ______________________________________________ >> 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. >> > ______________________________________________ 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.