Dear knowing people,
I have a data frame like this.
exdatframe <- data.frame(Name=c("Ernie","Ernie","Ernie",
"CookieMonster","CookieMonster","CookieMonster"),
recordedTime=as.POSIXct(strptime(as.character("01.01.2017","02.01.2011","03.01.2011",
"01.01.2011","02.01.2011","03.01.2011"),"%d.%m.%Y")),
week =c(1,2,2,
1,2,2),
eatencookies=c(1,0.5,0.001,
50,51,200))
exdatframe
#Now I want a new dataframe with only the first row per week (i.e. I
want to know how many cookies were eaten at the first recorded day of
each week). Something like that:
exdatframe2 <- data.frame(Name=c("Ernie","Ernie",
"CookieMonster","CookieMonster"),
recordedTime=c("01.01.2017","02.01.2011",
"01.01.2011","02.01.2011"),
week =c(1,2,
1,2),
eatencookies=c(1,0.5,
50,51))
exdatframe2
# How do I do that? I thought it must be something with tapply or subset
- but I just don't get it....
# would be great if someone helps.
# Dagmar
beginner question: subset first entry (row) per week
3 messages · Bert Gunter, Dagmar
new.df <- orig.df[!duplicated(df[["week"]]), ] See ?duplicated -- Bert Bert Gunter "The trouble with having an open mind is that people keep coming along and sticking things into it." -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )
On Thu, Feb 2, 2017 at 1:04 PM, Dagmar <Ramgad82 at gmx.net> wrote:
Dear knowing people,
I have a data frame like this.
exdatframe <- data.frame(Name=c("Ernie","Ernie","Ernie",
"CookieMonster","CookieMonster","CookieMonster"),
recordedTime=as.POSIXct(strptime(as.character("01.01.2017","02.01.2011","03.01.2011",
"01.01.2011","02.01.2011","03.01.2011"),"%d.%m.%Y")),
week =c(1,2,2,
1,2,2),
eatencookies=c(1,0.5,0.001,
50,51,200))
exdatframe
#Now I want a new dataframe with only the first row per week (i.e. I want to
know how many cookies were eaten at the first recorded day of each week).
Something like that:
exdatframe2 <- data.frame(Name=c("Ernie","Ernie",
"CookieMonster","CookieMonster"),
recordedTime=c("01.01.2017","02.01.2011",
"01.01.2011","02.01.2011"),
week =c(1,2,
1,2),
eatencookies=c(1,0.5,
50,51))
exdatframe2
# How do I do that? I thought it must be something with tapply or subset -
but I just don't get it....
# would be great if someone helps.
# Dagmar
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Dear all, Now, all the sudden I found the answer myself :-) I did it by: ddply(exdatframe,.(week),function(x) head(x,1)) I'll simply do it for Ernie and Cookiemonster seperate - that is not a big problem. Thanks anyway for your engagement in this group! Dagmar Am 02.02.2017 um 22:04 schrieb Dagmar:
Dear knowing people,
I have a data frame like this.
exdatframe <- data.frame(Name=c("Ernie","Ernie","Ernie",
"CookieMonster","CookieMonster","CookieMonster"),
recordedTime=as.POSIXct(strptime(as.character("01.01.2017","02.01.2011","03.01.2011",
"01.01.2011","02.01.2011","03.01.2011"),"%d.%m.%Y")),
week =c(1,2,2,
1,2,2),
eatencookies=c(1,0.5,0.001,
50,51,200))
exdatframe
#Now I want a new dataframe with only the first row per week (i.e. I
want to know how many cookies were eaten at the first recorded day of
each week). Something like that:
exdatframe2 <- data.frame(Name=c("Ernie","Ernie",
"CookieMonster","CookieMonster"),
recordedTime=c("01.01.2017","02.01.2011",
"01.01.2011","02.01.2011"),
week =c(1,2,
1,2),
eatencookies=c(1,0.5,
50,51))
exdatframe2
# How do I do that? I thought it must be something with tapply or
subset - but I just don't get it....
# would be great if someone helps.
# Dagmar