Filtering a dataframe in r row names from a second data frame in r
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I have the data.frame

    df1<-data.frame("Sp1"=1:6,"Sp2"=7:12,"Sp3"=13:18)
    rownames(df1)=c("A","B","C","D","E","F")

    df1

      Sp1 Sp2 Sp3
    A   1   7  13
    B   2   8  14
    C   3   9  15
    D   4  10  16
    E   5  11  17
    F   6  12  18

    #I filter df1 by a cutoff value for rowSums(df1) and return sites (row names) that I want to include in downstream analysis

    include<-rownames(df1[rowSums(df1)>=22,])
    include

    [1] "B" "C" "D" "E" "F"

    #I have a second data.frame
    df2<-data.frame(site.x=c("A","B","C"), site.y=c("D","E","F"),score=1:3)

      site.x site.y score
    1      A      D     1
    2      B      E     2
    3      C      F     3

    I want to filter df2 such that it only includes rows where df2$site.x and df2$site.y are exactly equal to the sites listed in 'include' i.e. filtering out the row containing "A" and returning

      site.x site.y score    
    2      B      E     2
    3      C      F     3


    #I have tried
    
    filter<-df1$site.x == include & df1$site.y == include	
		 
    filtered<-df1[filter,]

  Thanks for any advice!