Hi, I have two lists 1) List1- 30,000 rows and 104 columns 2) List2- a list of 14000 selected rownames from List 1 Now, I want to extract all the 104 columns of List1 matching with the 14000 selected rownames from List2. Psedocode will be something like this: match rownames(List2) with rownames(List1) extract selected matched 104 coloumns from (List1) strore in-> List3 So the resulting List3 will contain 14,000 rows and 104 coloumns. How do I do it in R ? Regards, P Barah Department of Biology, Norwegian University of Science & Technology (NTNU) Realfagbygget, N-7491 Trondheim, Norway [[alternative HTML version deleted]]
On Tue, Feb 08, 2011 at 08:27:38PM +0530, pankaj borah wrote:> Hi, > > I have two lists > > 1) List1- 30,000 rows and 104 columns > > 2) List2- a list of 14000 selected rownames? from List 1 > > Now, I want to extract all the 104 columns of List1? matching with the 14000 selected rownames from List2.? > > Psedocode will be something like this: > match rownames(List2) with rownames(List1) > extract selected matched 104 coloumns from (List1) > strore in-> List3 > > So the resulting List3 will contain 14,000 rows and 104 coloumns. > > How do I do it in R ?Hi. Let me use a small example df <- data.frame(a=1:7, b=11:17, row.names=letters[1:7]) df a b a 1 11 b 2 12 c 3 13 d 4 14 e 5 15 f 6 16 g 7 17 Is the following what you are asking for in terms of this small example? df[c("b", "c", "g"), ] a b b 2 12 c 3 13 g 7 17 Petr Savicky.
Hi:
Try some modification of the following toy example:
df <- data.frame(names = as.character(replicate(100, paste(sample(letters,
3), collapse = ''))),
x1 = rnorm(100), x2 = rnorm(100))
tgts <- sample(df$names, 20) # target list of names
df[df$names %in% tgts, ] # yields a 20 row data frame
HTH,
Dennis
On Tue, Feb 8, 2011 at 6:57 AM, pankaj borah
<pankajborah2k3@yahoo.co.in>wrote:
> Hi,
>
> I have two lists
>
> 1) List1- 30,000 rows and 104 columns
>
> 2) List2- a list of 14000 selected rownames from List 1
>
> Now, I want to extract all the 104 columns of List1 matching with the
> 14000 selected rownames from List2.
>
> Psedocode will be something like this:
> match rownames(List2) with rownames(List1)
> extract selected matched 104 coloumns from (List1)
> strore in-> List3
>
> So the resulting List3 will contain 14,000 rows and 104 coloumns.
>
> How do I do it in R ?
>
>
>
> Regards,
>
> P Barah
> Department of Biology,
> Norwegian University of Science & Technology (NTNU)
> Realfagbygget, N-7491 Trondheim, Norway
>
>
>
> [[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]]