Hi, I am a little new in R but I'm finding it extremely useful :) Here's my tiny question: I've got a table with a lot of columns. What I am interested now is to evaluate how many of 4 columns have a value greater than 1. I think it can be done with subset() but it will take a very long condition and become unfeasible if I want to compare more than 4 columns. I put here a small example Col1 Col2 Col3 Col 4 1 1 1 1 <-0 columns greater than 1 2 1 1 1 <-1 column greater than 1 4 1 4 1 <-2 columns greater than 1 3 3 3 3 <-3 columns greater than 1 Then I want to filter by that number, my idea is to create a new column storing the number calculated and subset() by it. Any hints? Thanks in advance JL [[alternative HTML version deleted]]
Hi JL, How about the following? rowSums(d >1) # d is your data Best, Jorge.- On Thu, Nov 10, 2011 at 10:24 AM, JL Villanueva <> wrote:> Hi, > > I am a little new in R but I'm finding it extremely useful :) > > Here's my tiny question: > > I've got a table with a lot of columns. What I am interested now is to > evaluate how many of 4 columns have a value greater than 1. > I think it can be done with subset() but it will take a very long condition > and become unfeasible if I want to compare more than 4 columns. > > I put here a small example > > Col1 Col2 Col3 Col 4 > 1 1 1 1 <-0 columns greater than 1 > 2 1 1 1 <-1 column greater than 1 > 4 1 4 1 <-2 columns greater than 1 > 3 3 3 3 <-3 columns greater than 1 > > Then I want to filter by that number, my idea is to create a new column > storing the number calculated and subset() by it. > > Any hints? > Thanks in advance > > JL > > [[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]]
try this:> xCol1 Col2 Col3 Col4 1 1 1 1 1 2 2 1 1 1 3 4 1 4 1 4 3 3 3 3> apply(x, 1, function(a) sum(a > 1))[1] 0 1 2 4> x$count <- apply(x, 1, function(a) sum(a > 1)) > xCol1 Col2 Col3 Col4 count 1 1 1 1 1 0 2 2 1 1 1 1 3 4 1 4 1 2 4 3 3 3 3 4>On Thu, Nov 10, 2011 at 10:24 AM, JL Villanueva <jlpostage at gmail.com> wrote:> Hi, > > I am a little new in R but I'm finding it extremely useful :) > > Here's my tiny question: > > I've got a table with a lot of columns. What I am interested now is to > evaluate how many of 4 columns have a value greater than 1. > I think it can be done with subset() but it will take a very long condition > and become unfeasible if I want to compare more than 4 columns. > > I put here a small example > > Col1 ?Col2 ?Col3 ?Col 4 > 1 ? ? ? ?1 ? ? ? 1 ? ? ? 1 ? ? ? ? ? ? <-0 columns greater than 1 > 2 ? ? ? ?1 ? ? ? 1 ? ? ? 1 ? ? ? ? ? ? <-1 column greater than 1 > 4 ? ? ? ?1 ? ? ? 4 ? ? ?1 ? ? ? ? ? ? ?<-2 columns greater than 1 > 3 ? ? ? ?3 ? ? ? 3 ? ? ? 3 ? ? ? ? ? ? <-3 columns greater than 1 > > Then I want to filter by that number, my idea is to create a new column > storing the number calculated and subset() by it. > > Any hints? > Thanks in advance > > JL > > ? ? ? ?[[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. >-- Jim Holtman Data Munger Guru What is the problem that you are trying to solve? Tell me what you want to do, not how you want to do it.
Hi:
Here's a toy example:
# Default var names are V1-V20:
u <- as.data.frame(matrix(rpois(100, 3), ncol = 20))
u <- transform(u,
ngt1 = apply(u[, c('V1', 'V4', 'V9',
'V15')], 1, function(x) sum(x > 1)) )
u
HTH,
Dennis
On Thu, Nov 10, 2011 at 7:24 AM, JL Villanueva <jlpostage at gmail.com>
wrote:> Hi,
>
> I am a little new in R but I'm finding it extremely useful :)
>
> Here's my tiny question:
>
> I've got a table with a lot of columns. What I am interested now is to
> evaluate how many of 4 columns have a value greater than 1.
> I think it can be done with subset() but it will take a very long condition
> and become unfeasible if I want to compare more than 4 columns.
>
> I put here a small example
>
> Col1 ?Col2 ?Col3 ?Col 4
> 1 ? ? ? ?1 ? ? ? 1 ? ? ? 1 ? ? ? ? ? ? <-0 columns greater than 1
> 2 ? ? ? ?1 ? ? ? 1 ? ? ? 1 ? ? ? ? ? ? <-1 column greater than 1
> 4 ? ? ? ?1 ? ? ? 4 ? ? ?1 ? ? ? ? ? ? ?<-2 columns greater than 1
> 3 ? ? ? ?3 ? ? ? 3 ? ? ? 3 ? ? ? ? ? ? <-3 columns greater than 1
>
> Then I want to filter by that number, my idea is to create a new column
> storing the number calculated and subset() by it.
>
> Any hints?
> Thanks in advance
>
> JL
>
> ? ? ? ?[[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.
>