R help - Aug 2012 - Subsetting rows by multiple levels of selected values

Dear list,

Let's say we have a data frame as follows,
>expand.grid(a=1:5,b=c(1,5,10,20),DV=c(0.1,0.2,0.3))->df1
>df1$DV<-rgamma(60,shape=10)
columns a and b are two levels. DV is the column with values we are
interested in.

Then another data frame df2 with values as follows

data.frame(a=c(2,2,3,4,5),b=c(5,10,1,5,20))->df2

Now I want to a subset of df1 that match df2 at the both columns a and b.
Any idea?

Thanks.

Jun

	[[alternative HTML version deleted]]

Hi Jun,

I think

merge(df1, df2)

should do it.

Best,
Ista

On Tue, Aug 14, 2012 at 3:05 PM, Jun Shen <jun.shen.ut at gmail.com>
wrote:
> Dear list,
>
> Let's say we have a data frame as follows,
>
>>expand.grid(a=1:5,b=c(1,5,10,20),DV=c(0.1,0.2,0.3))->df1
>>df1$DV<-rgamma(60,shape=10)
>
> columns a and b are two levels. DV is the column with values we are
> interested in.
>
> Then another data frame df2 with values as follows
>
> data.frame(a=c(2,2,3,4,5),b=c(5,10,1,5,20))->df2
>
> Now I want to a subset of df1 that match df2 at the both columns a and b.
> Any idea?
>
> Thanks.
>
> Jun
>
>         [[alternative HTML version deleted]]
>
> ______________________________________________
> 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.

Hello,

Try the following.

df3 <- merge(df2, df1)

Hope this helps,

Rui Barradas

Em 14-08-2012 20:05, Jun Shen escreveu:
> Dear list,
>
> Let's say we have a data frame as follows,
>
>> expand.grid(a=1:5,b=c(1,5,10,20),DV=c(0.1,0.2,0.3))->df1
>> df1$DV<-rgamma(60,shape=10)
> columns a and b are two levels. DV is the column with values we are
> interested in.
>
> Then another data frame df2 with values as follows
>
> data.frame(a=c(2,2,3,4,5),b=c(5,10,1,5,20))->df2
>
> Now I want to a subset of df1 that match df2 at the both columns a and b.
> Any idea?
>
> Thanks.
>
> Jun
>
> 	[[alternative HTML version deleted]]
>
> ______________________________________________
> 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.

merge(df1,df2)

--- On Wed, 15/8/12, Jun Shen <jun.shen.ut@gmail.com> wrote:


From: Jun Shen <jun.shen.ut@gmail.com>
Subject: [R] Subsetting rows by multiple levels of selected values
To: "R-help" <r-help@stat.math.ethz.ch>
Date: Wednesday, 15 August, 2012, 12:35 AM


Dear list,

Let's say we have a data frame as follows,
>expand.grid(a=1:5,b=c(1,5,10,20),DV=c(0.1,0.2,0.3))->df1
>df1$DV<-rgamma(60,shape=10)
columns a and b are two levels. DV is the column with values we are
interested in.

Then another data frame df2 with values as follows

data.frame(a=c(2,2,3,4,5),b=c(5,10,1,5,20))->df2

Now I want to a subset of df1 that match df2 at the both columns a and b.
Any idea?

Thanks.

Jun

    [[alternative HTML version deleted]]

______________________________________________
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.

	[[alternative HTML version deleted]]

HI,

In addition to merge(), you can also use:?join()
library(plyr)
join(df1,df2,type="inner")

A.K.


----- Original Message -----
From: Jun Shen <jun.shen.ut at gmail.com>
To: R-help <r-help at stat.math.ethz.ch>
Cc: 
Sent: Tuesday, August 14, 2012 3:05 PM
Subject: [R] Subsetting rows by multiple levels of selected values

Dear list,

Let's say we have a data frame as follows,
>expand.grid(a=1:5,b=c(1,5,10,20),DV=c(0.1,0.2,0.3))->df1
>df1$DV<-rgamma(60,shape=10)
columns a and b are two levels. DV is the column with values we are
interested in.

Then another data frame df2 with values as follows

data.frame(a=c(2,2,3,4,5),b=c(5,10,1,5,20))->df2

Now I want to a subset of df1 that match df2 at the both columns a and b.
Any idea?

Thanks.

Jun

??? [[alternative HTML version deleted]]

______________________________________________
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.