Darren Norris
2008-Mar-06 22:00 UTC
[R] can't merge zoo ojects and convert to ts (been trying for 2 days)
I'm stuck, but am sure it can be done I just don't understand how. I have data in an irregular timeseries. I want to be able to use stl to visualise the data (see seasonal parts etc), so I need to change to regular series of class ts (I think). I am using 2 zoo objects one is regular and the other is my irregular data. I am then merging to create the object I want but when I try to change to a ts class using as.ts I get the following error: Error in zoo(coredata(x), tt) : ?x? : attempt to define illegal zoo object. Can anyone show the error of my ways? I have looked throuh help and the zoo pdf's but can't see the answer. Many thanks for any help. All code and data below (short example). Darren R version 2.6.1 (2007-11-26) i386-pc-mingw32 locale: LC_COLLATE=English_United Kingdom.1252;LC_CTYPE=English_United Kingdom.1252;LC_MONETARY=English_United Kingdom.1252;LC_NUMERIC=C;LC_TIME=English_United Kingdom.1252 attached base packages: [1] stats graphics grDevices utils datasets methods base other attached packages: [1] chron_2.3-21 zoo_1.4-2 loaded via a namespace (and not attached): [1] grid_2.6.1 lattice_0.17-2 tools_2.6.1 ###Import data: ttest<-read.csv("la_time_test2.csv", header = T, as.is=TRUE); tlist<-read.csv("la_time_list2.csv", header = T, as.is=TRUE) ####Convert to zoo: zooreg_time<-zoo(, as.chron(strptime(tlist$a_datetime, format="%d/%m/%Y %H"), format = c(dates = "Y-m-d ", times = "H:M:S")),frequency=8760 ) class(zooreg_time) [1] "zooreg" "zoo" ###Create my zoo objects ###First irregular series. Steps: 1) create vector to order by 2) create zoo object. #####Vector to order by:>zoo_test<- as.chron(strptime(ttest$Ruta_datetime_start, format="%d/%m/%Y%H"), format = c(dates = "Y-m-d ", times = "H:M:S")) zoo_test [1] (2004-Apr-28 08:00:00) (2004-Apr-28 13:00:00) #####Zoo object: zoo_test2<-zoo(ttest$Minutos.de.viaje,zoo_test) zoo_test2 (2004-Apr-28 08:00:00) (2004-Apr-28 13:00:00) 125 295 #####Merge (need to approximate NAs so can change to ts?) x<-na.approx(merge(zooreg_time,zoo_test2)) x (2004-Apr-28 08:00:00) (2004-Apr-28 09:00:00) (2004-Apr-28 10:00:00) (2004-Apr-28 11:00:00) (2004-Apr-28 12:00:00) (2004-Apr-28 13:00:00) 125 159 193 227 261 295 ######Now change to ts as.ts(x) Error in zoo(coredata(x), tt) : ?x? : attempt to define illegal zoo object THE DATA la_time_test2.csv TRIP_ID Ruta_datetime_start Minutos de viaje 28/04/2004_CM2-CM1_downriver_08:15 28/04/2004 08:15 125 28/04/2004_CM1-CM2_upriver_13:05 28/04/2004 13:05 295 la_time_list2.csv a_datetime 28/04/2004 01:00 28/04/2004 02:00 28/04/2004 03:00 28/04/2004 04:00 28/04/2004 05:00 28/04/2004 06:00 28/04/2004 07:00 28/04/2004 08:00 28/04/2004 09:00 28/04/2004 10:00 28/04/2004 11:00 28/04/2004 12:00 28/04/2004 13:00 28/04/2004 14:00 28/04/2004 15:00 28/04/2004 16:00 28/04/2004 17:00 ttest TRIP_ID Ruta_datetime_start Minutos.de.viaje 1 28/04/2004_CM2-CM1_downriver_08:15 28/04/2004 08:15 125 2 28/04/2004_CM1-CM2_upriver_13:05 28/04/2004 13:05 295 tlist a_datetime 1 28/04/2004 01:00 2 28/04/2004 02:00 3 28/04/2004 03:00 4 28/04/2004 04:00 5 28/04/2004 05:00 6 28/04/2004 06:00 7 28/04/2004 07:00 8 28/04/2004 08:00 9 28/04/2004 09:00 10 28/04/2004 10:00 11 28/04/2004 11:00 12 28/04/2004 12:00 13 28/04/2004 13:00 14 28/04/2004 14:00 15 28/04/2004 15:00 16 28/04/2004 16:00 17 28/04/2004 17:00 zooreg_time Data: numeric(0) Index: [1] (2004-Apr-28 01:00:00) (2004-Apr-28 02:00:00) (2004-Apr-28 03:00:00) (2004-Apr-28 04:00:00) (2004-Apr-28 05:00:00) (2004-Apr-28 06:00:00) [7] (2004-Apr-28 07:00:00) (2004-Apr-28 08:00:00) (2004-Apr-28 09:00:00) (2004-Apr-28 10:00:00) (2004-Apr-28 11:00:00) (2004-Apr-28 12:00:00) [13] (2004-Apr-28 13:00:00) (2004-Apr-28 14:00:00) (2004-Apr-28 15:00:00) (2004-Apr-28 16:00:00) (2004-Apr-28 17:00:00) x (2004-Apr-28 08:00:00) (2004-Apr-28 09:00:00) (2004-Apr-28 10:00:00) (2004-Apr-28 11:00:00) (2004-Apr-28 12:00:00) (2004-Apr-28 13:00:00) 125 159 193 227 261 295 -- View this message in context: http://www.nabble.com/can%27t-merge-zoo-ojects-and-convert-to-ts-%28been-trying-for-2-days%29-tp15885132p15885132.html Sent from the R help mailing list archive at Nabble.com.
Gabor Grothendieck
2008-Mar-07 02:42 UTC
[R] can't merge zoo ojects and convert to ts (been trying for 2 days)
Its a bug in na.approx. I just fixed it and (1) until a new version of zoo comes out add this to your code: source("http://r-forge.r-project.org/plugins/scmsvn/viewcvs.php/*checkout*/pkg/R/na.approx.R?rev=448&root=zoo") or (2) a workaround not requiring that source statement is to add the na.rm = FALSE argument to na.approx since the bug only gets triggered with the default na.rm = TRUE setting. Actually in your case you don't need na.approx anyways since as.ts can do it all itself and if you want to force a specific frequency (rather than the one it picks) you can convert to zooreg first specifying that frequency. Also please try to provide code in such a manner that one can simply copy it from the post and paste it into one's R session to reproduce the problem using the style shown below. I have also illustrated some simplifications: library(zoo) library(chron) la_time_test2 <- "TRIP_ID,Ruta_datetime_start,Minutos de viaje 28/04/2004_CM2-CM1_downriver_08:15,28/04/2004 08:15,125 28/04/2004_CM1-CM2_upriver_13:05,28/04/2004 13:05,295 " t.df <- read.csv(textConnection(la_time_test2)) t.zoo <- zoo(test2.df[,3], as.chron(strptime(test2.df[,2], "%d/%m/%Y %H:%M"))) t.ts <- as.ts(as.zooreg(test2.zoo, freq = 24 * 365)) On Thu, Mar 6, 2008 at 5:00 PM, Darren Norris <doon75 at hotmail.com> wrote:> > I'm stuck, but am sure it can be done I just don't understand how. > I have data in an irregular timeseries. I want to be able to use stl to > visualise the data (see seasonal parts etc), so I need to change to regular > series of class ts (I think). > > I am using 2 zoo objects one is regular and the other is my irregular data. > I am then merging to create the object I want but when I try to change to a > ts class using as.ts I get the following error: > Error in zoo(coredata(x), tt) : > "x" : attempt to define illegal zoo object. > > Can anyone show the error of my ways? I have looked throuh help and the zoo > pdf's but can't see the answer. > Many thanks for any help. > All code and data below (short example). > Darren > > R version 2.6.1 (2007-11-26) > i386-pc-mingw32 > > locale: > LC_COLLATE=English_United Kingdom.1252;LC_CTYPE=English_United > Kingdom.1252;LC_MONETARY=English_United > Kingdom.1252;LC_NUMERIC=C;LC_TIME=English_United Kingdom.1252 > > attached base packages: > [1] stats graphics grDevices utils datasets methods base > > other attached packages: > [1] chron_2.3-21 zoo_1.4-2 > > loaded via a namespace (and not attached): > [1] grid_2.6.1 lattice_0.17-2 tools_2.6.1 > > ###Import data: > ttest<-read.csv("la_time_test2.csv", header = T, as.is=TRUE); > tlist<-read.csv("la_time_list2.csv", header = T, as.is=TRUE) > > ####Convert to zoo: > zooreg_time<-zoo(, as.chron(strptime(tlist$a_datetime, format="%d/%m/%Y > %H"), format = c(dates = "Y-m-d ", times = "H:M:S")),frequency=8760 ) > class(zooreg_time) > [1] "zooreg" "zoo" > > ###Create my zoo objects > ###First irregular series. Steps: 1) create vector to order by 2) create zoo > object. > > #####Vector to order by: > > >zoo_test<- as.chron(strptime(ttest$Ruta_datetime_start, format="%d/%m/%Y > %H"), format = c(dates = "Y-m-d ", times = "H:M:S")) > zoo_test > [1] (2004-Apr-28 08:00:00) (2004-Apr-28 13:00:00) > > #####Zoo object: > zoo_test2<-zoo(ttest$Minutos.de.viaje,zoo_test) > zoo_test2 > (2004-Apr-28 08:00:00) (2004-Apr-28 13:00:00) > 125 295 > > #####Merge (need to approximate NAs so can change to ts?) > x<-na.approx(merge(zooreg_time,zoo_test2)) > x > (2004-Apr-28 08:00:00) (2004-Apr-28 09:00:00) (2004-Apr-28 10:00:00) > (2004-Apr-28 11:00:00) (2004-Apr-28 12:00:00) (2004-Apr-28 13:00:00) > 125 159 193 > 227 261 295 > > ######Now change to ts > as.ts(x) > Error in zoo(coredata(x), tt) : > "x" : attempt to define illegal zoo object > > THE DATA > la_time_test2.csv > TRIP_ID Ruta_datetime_start Minutos de viaje > 28/04/2004_CM2-CM1_downriver_08:15 28/04/2004 08:15 125 > 28/04/2004_CM1-CM2_upriver_13:05 28/04/2004 13:05 295 > > la_time_list2.csv > a_datetime > 28/04/2004 01:00 > 28/04/2004 02:00 > 28/04/2004 03:00 > 28/04/2004 04:00 > 28/04/2004 05:00 > 28/04/2004 06:00 > 28/04/2004 07:00 > 28/04/2004 08:00 > 28/04/2004 09:00 > 28/04/2004 10:00 > 28/04/2004 11:00 > 28/04/2004 12:00 > 28/04/2004 13:00 > 28/04/2004 14:00 > 28/04/2004 15:00 > 28/04/2004 16:00 > 28/04/2004 17:00 > > ttest > TRIP_ID Ruta_datetime_start Minutos.de.viaje > 1 28/04/2004_CM2-CM1_downriver_08:15 28/04/2004 08:15 125 > 2 28/04/2004_CM1-CM2_upriver_13:05 28/04/2004 13:05 295 > > tlist > a_datetime > 1 28/04/2004 01:00 > 2 28/04/2004 02:00 > 3 28/04/2004 03:00 > 4 28/04/2004 04:00 > 5 28/04/2004 05:00 > 6 28/04/2004 06:00 > 7 28/04/2004 07:00 > 8 28/04/2004 08:00 > 9 28/04/2004 09:00 > 10 28/04/2004 10:00 > 11 28/04/2004 11:00 > 12 28/04/2004 12:00 > 13 28/04/2004 13:00 > 14 28/04/2004 14:00 > 15 28/04/2004 15:00 > 16 28/04/2004 16:00 > 17 28/04/2004 17:00 > > zooreg_time > Data: > numeric(0) > Index: > [1] (2004-Apr-28 01:00:00) (2004-Apr-28 02:00:00) (2004-Apr-28 03:00:00) > (2004-Apr-28 04:00:00) (2004-Apr-28 05:00:00) (2004-Apr-28 06:00:00) > [7] (2004-Apr-28 07:00:00) (2004-Apr-28 08:00:00) (2004-Apr-28 09:00:00) > (2004-Apr-28 10:00:00) (2004-Apr-28 11:00:00) (2004-Apr-28 12:00:00) > [13] (2004-Apr-28 13:00:00) (2004-Apr-28 14:00:00) (2004-Apr-28 15:00:00) > (2004-Apr-28 16:00:00) (2004-Apr-28 17:00:00) > > > x > (2004-Apr-28 08:00:00) (2004-Apr-28 09:00:00) (2004-Apr-28 10:00:00) > (2004-Apr-28 11:00:00) (2004-Apr-28 12:00:00) (2004-Apr-28 13:00:00) > 125 159 193 > 227 261 295 > > > -- > View this message in context: http://www.nabble.com/can%27t-merge-zoo-ojects-and-convert-to-ts-%28been-trying-for-2-days%29-tp15885132p15885132.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help at 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. >