On Dec 7, 2018, at 7:18 PM, Dagmar Cimiotti <dagmar.cimiotti at ftz-west.uni-kiel.de> wrote:
Hi Jim and everyone else,
Mhm, no this is not what I am looking for. I think in your way I would
randomly sample two values of day 1 and of day 2. But I want the
opposite: I want to randomly draw two successive (!) days and put those
values in a new dataframe to continue working with them.
In my real data I do have a huge time span and I want to draw 25
consecutive days. So maybe my example was a little misleading. And now
that I read it again my text was, too. Sorry about that!
Good try though and I am very gratefull for your good will to help me
Would anyone give another try?
Dagmar
Am 07.12.2018 um 10:30 schrieb Jim Lemon:
Hi Dagmar,
This will probably involve creating a variable to differentiate the
two days in each data.frame:
myframe$day<-as.Date(as.character(myframe$Timestamp),"%d.%m.%Y %H:%M:%S")
days<-unique(myframe$day)
Then just sample the two subsets and concatenate them:
myframe[c(sample(which(myframe$day==days[1]),2),
sample(which(myframe$day==days[2]),2)),]
Jim
On Fri, Dec 7, 2018 at 8:08 PM Dagmar Cimiotti
<dagmar.cimiotti at ftz-west.uni-kiel.de> wrote:
Dear all,
I have data from a time span like this:
myframe <- data.frame (Timestamp=c("24.09.2012 09:00:00", "24.09.2012
10:00:00","25.09.2012 09:00:00",
"25.09.2012
09:00:00","24.09.2012 09:00:00", "24.09.2012 10:00:00"),
Event=c(50,60,30,40,42,54) )
myframe
I want to create a new dataframe which includes in this example the
data from two successive days (in my real data I have a big time span
and want data from 25 consecutive days). I understand that I can do a
simple sample like this
mysample <- myframe[sample(1:nrow(myframe), 4,replace=FALSE),]
mysample
But I need the data from consecutive days in my random sample. Can
anyone help me with this?
Many thanks in advance,
Dagmar