[R] subset rows in two dataframes

[Zhuanshi He]

Dear Jim,

Maybe u want this,

> subset(dat2, time1 %in% dat2$v1 & time2 %in% dat2$v1)
           v1     v2
2  2006-05-09 7065.0
3  2006-05-04 3622.5
5  2006-07-14 3532.5
7  2006-05-12 6480.0
8  2006-05-17 4612.5
15 2006-07-05 4837.5
16 2006-07-06 3352.5
18 2006-07-24 6772.5
20 2006-07-18 5625.0
Warning message:
In time1 %in% dat2$v1 & time2 %in% dat2$v1 :
  longer object length is not a multiple of shorter object length



However, it looks the length of time1 and time2 is different.

--------------------------------------------------------------------------------------------------------------

On 5/11/08, partofy at inoutbox.com <partofy at inoutbox.com> wrote:
>
>  Dear list:
>
>  I can now reproduce with a bit of my real data, the problem I asked for
>  your help yestarday:
>
>  time1<- as.Date(c("2006-01-03", "2006-05-03", "2006-05-04",
>  "2006-05-11", "2006-05-12", "2006-05-16", "2006-05-19", "2006-05-26",
>  "2006-09-15", "2006-10-30", "2006-11-08", "2006-11-14", "2006-11-20"))
>  volume1<- c(7312.5, 3352.5, 4252.5, 3825.0, 2700.0, 585.0, 810.0,
>  3015.0, 2925.0, 1102.5, 2632.5, 652.5, 1417.5)
>  dat1<- data.frame(v1=time1, v2=volume1)
>
>  time2<- as.Date(c("2006-05-03", "2006-05-09", "2006-05-04",
>  "2006-05-08", "2006-07-14", "2006-07-10", "2006-05-12", "2006-05-17",
>  "2006-05-19", "2006-05-26", "2006-05-29", "2006-05-18", "2006-05-22",
>  "2006-07-03", "2006-07-05", "2006-07-06", "2006-07-04", "2006-07-24",
>  "2006-07-12", "2006-07-18"))
>  volume2<- c(4522.5, 7065.0, 3622.5, 7875.0, 3532.5, 3667.5, 6480.0,
>  4612.5, 4005.0, 10350.0, 5310.0, 6345.0, 7177.5, 5107.5, 4837.5, 3352.5,
>  4050.0, 6772.5, 7290.0, 5625.0)
>  dat2<- data.frame(v1=time2, v2=volume2)
>
>  subset(dat1, v1 %in% dat2$v1 & v2 %in% dat2$v2)
>           v1     v2
>  2 2006-05-03 3352.5
>
>  This is not what I expect since this row is not present in dat2 and I
>  just want records present in both dataframes.
>
>  Help?
>
>  J
>
>
>
>
>
>
>  On Sat, 10 May 2008 18:42:51 -0400, "jim holtman" <jholtman at gmail.com>
>  said:
>
> > This seems to work for me:
>  >
>  > > set.seed(1)
>  > > df1 <- data.frame(v1=factor(sample(1:4,20,TRUE)), v2=factor(sample(1:3,20,TRUE)), v3=sample(1:3,20,TRUE))
>  > > df2 <- data.frame(v1=factor(sample(1:2,20,TRUE)), v2=factor(sample(1:2,20,TRUE)), v3=sample(1:2,20,TRUE))
>  > > subset(df1, (df1$v1 %in% df2$v1) & (df1$v2 %in% df2$v2) & (df1$v3 %in% df2$v3))
>  >    v1 v2 v3
>  > 2   2  1  2
>  > 5   1  1  2
>  > 11  1  2  2
>  > 14  2  1  1
>  > >
>  >
>  > Exactly what problems are you having?  A sample of your actual data
>  > would be useful.
>  >
>  > On Sat, May 10, 2008 at 6:31 PM,  <partofy at inoutbox.com> wrote:
>  > > Dear list:
>  > >
>  > > I have two dataframes, say dat1 and dat2. Each has several variables but
>  > > 3 of each are common in both, (say v1, v2 and v3). v1 and v2 are
>  > > factores while v3 is numeric. Now, I need a subset to extract the rows
>  > > in which v1, v2 and v3 are the same in both dataframes.
>  > > I tried:
>  > >
>  > > subset(dat1, dat1$v1 %in% dat2$v1 & dat1$v2 %in% dat2$v2 & dat1$v3 %in%
>  > > dat2$v3)
>  > >
>  > > I dont know why, but this is not working as I was expecting. Any
>  > > suggestion to improve my code?
>  > >
>  > > Thanks in advance
>  > >
>  > > Justin
>  > > --
>  > >
>  > >  partofy at inoutbox.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.
>  > >
>  >
>  >
>  >
>  > --
>  > Jim Holtman
>  > Cincinnati, OH
>  > +1 513 646 9390
>  >
>  > What is the problem you are trying to solve?
>
> --
>
>
>   partofy at inoutbox.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.
>
>
>


-- 
Zhuanshi He / Z. He (PhD)
Waterloo Centre for Atmospheric Sciences (WCAS)
Department of Earth and Environmental Sciences
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University of Waterloo,
Waterloo, ON N2L 3G1
Canada
Tel: +1-519-888-4567 ext 38053        FAX: +1-519-746-0435