Hello,
The trick is to use seq() for date classes.
First of all, when creating data.frames use stringsAsFactors=FALSE, in
order not to convert them to factors. I've added this option to your
data.frame() instructions. And then,
mydata1$dates <- as.POSIXct(mydata1$dates)
mydata1b$dates <- as.POSIXct(mydata1b$dates)
mydata2$dates <- as.POSIXct(mydata2$dates)
mydata2b$dates <- as.POSIXct(mydata2b$dates)
Now, first we create the sequences then use merge(9, that will take care
of inserting the NAs.
# mydata1
tmp <- tapply(mydata1$dates, format(mydata1$dates, "%Y-%m-%d"),
function(x){
if(length(x) < 2) paste(format(x, "%Y-%m-%d"),
c("07:00:00", "19:00:00"))
else sub("0 [[:alpha:]]+$", "", x)
})
tmp <- as.POSIXct(unlist(tmp))
merge(mydata1, data.frame(dates=tmp), all.y=TRUE)
# and mydata2
tmp <- data.frame(dates=seq(mydata2$dates[1], mydata2$dates[n], by="10
mins"))
merge(mydata2, tmp, all.y=TRUE)
Hope this helps,
Rui Barradas
Em 03-07-2012 10:52, ??????????? ????????? escreveu:> Hello
> I have dataframes.
> mydata1 <-data.frame(value=c(15,20,25,30,45,50),dates=c("2005-05-25
07:00:00
> ","2005-05-25 19:00:00","2005-06-25
07:00:00","2005-06-25 19:00:00
> ","2005-07-25 07:00:00","2005-8-25 19:00:00"))
> or
> mydata2 <-data.frame(value=c(15,20,25,30,45,50),dates=c("2005-05-25
00:00:00
> ","2005-05-25 00:10:00","2005-05-25
00:30:00","2005-05-25 00:40:00
> ","2005-05-25 00:50:00","2005-5-25 01:10:00"))
>
> I have to get such dataframes
>
> mydata1
<-data.frame(value=c(15,20,25,30,45,NA,NA,50),dates=c("2005-05-25
> 07:00:00","2005-05-25 19:00:00","2005-06-25
07:00:00","2005-06-25 19:00:00
> ","2005-07-25 07:00:00","2005-07-25
19:00:00","2005-8-25 07:00:00",
> "2005-8-25 19:00:00"))
> or
> mydata2
<-data.frame(value=c(15,20,NA,25,30,45,NA,50),dates=c("2005-05-25
> 00:00:00","2005-05-25 00:10:00","2005-05-25
00:20:00","2005-05-25 00:30:00
> ","2005-05-25 00:40:00","2005-05-25
00:50:00","2005-5-25 01:00:00",
> "2005-5-25 01:10:00"))
>
> Regards, Aleksander.
>
> [[alternative HTML version deleted]]
>
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