Its a bug. Its now fixed it in the development source so try this: library(chron)
library(zoo) source("http://r-forge.r-project.org/plugins/scmsvn/viewcvs.php/*checkout*/pkg/zoo/R/na.approx.R?rev=653&root=zoo") source("http://r-forge.r-project.org/plugins/scmsvn/viewcvs.php/*checkout*/pkg/zoo/R/zoo.R?rev=653&root=zoo") z1 <- structure(1:4, index = structure(c(0.0423611111111111, 0.0428819444444444, 0.0434027777777778, 0.0439236111111111), format = "h:m:s", class = "times"), class = "zoo") z2 <- structure(c(11L, 22L, 33L, 44L, 55L, 66L, 77L, 88L), .Dim = c(4L, 2L), .Dimnames = list(NULL, c("data", "data.1")), index = structure(c(0.0423726851851852, 0.0424074074074074, 0.0424421296296296, 0.0424768518518518), format = "h:m:s", class = "times"), class = "zoo") out1 <- na.approx(merge(z1, z2), time(z1)); out1 out2 <- na.approx(merge(z1, z2), time(z1), na.rm = FALSE); out2 out3 <- na.approx(merge(z1, z2), time(z1), rule = 2); out3 out4 <- na.approx(merge(z1, z2)); out4 out5 <- na.approx(merge(z1, z2), na.rm = FALSE); out5 out6 <- na.approx(merge(z1, z2), rule = 2); out6 The above style (which uses the output of dput to form z1 and z2) or the style requested in my last response using textConnection allows one to copy and paste directly into one's session (rather than having to download two files, copying and pasting to an editor, editing the paths and finally copying and pasting to R). On Sat, Jan 30, 2010 at 6:08 AM, e-letter <inp...@gmail.com> wrote: >> library(chron) >> library(zoo) >> z1<-read.zoo("~/path/to/test1.csv",header=TRUE,sep=",",FUN=times) >> z2<-read.zoo("~/path/to/test2.csv",header=TRUE,sep=",",FUN=times) >> z3<-(na.approx(merge(z1,z2),time(z1))) > Error in approx(along[!na], y[!na], along[na], ...) : > need at least two non-NA values to interpolate >> z3<-(na.approx(merge(z1,z2[,2]),time(z1))) > Error in approx(along[!na], y[!na], along[na], ...) : > need at least two non-NA values to interpolate >> z3<-(na.approx(merge(z1,z2[,3]),time(z1))) > Error in `[.zoo`(z2, , 3) : subscript out of bounds >> z4<-read.zoo(textConnection(z2),FUN=times) > Error in textConnection(z2) : invalid 'text' argument > ______________________________________________ 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.