Deleting reversed duplicates with R

Question

I have a data frame in R that contains the gene ids of paralogous genes in Arabidopsis, looking something like this:

gene_x    gene_y
AT1            


        

Answer 1

A dplyr possibility could be:

mydf %>%
 group_by(grp = paste(pmax(gene_x, gene_y), pmin(gene_x, gene_y), sep = "_")) %>%
 slice(1) %>%
 ungroup() %>%
 select(-grp)

  gene_x gene_y
     
1 AT1    AT2   
2 AT1    AT3   
3 AT3    AT4  

Or:

mydf %>%
 group_by(grp = paste(pmax(gene_x, gene_y), pmin(gene_x, gene_y), sep = "_")) %>%
 filter(row_number() == 1) %>%
 ungroup() %>%
 select(-grp)

Or:

mydf %>%
 group_by(grp = paste(pmax(gene_x, gene_y), pmin(gene_x, gene_y), sep = "_")) %>%
 distinct(grp, .keep_all = TRUE) %>%
 ungroup() %>%
 select(-grp)

Or using dplyr and purrr:

mydf %>%
 group_by(grp = paste(invoke(pmax, .), invoke(pmin, .), sep = "_")) %>%
 slice(1) %>%
 ungroup() %>%
 select(-grp)

And as of purrr 0.3.0 invoke() is retired, exec() should be used instead:

mydf %>%
 group_by(grp = paste(exec(pmax, !!!.), exec(pmin, !!!.), sep = "_")) %>%
 slice(1) %>%
 ungroup() %>%
 select(-grp)

Or:

df %>%
 rowwise() %>%
 mutate(grp = paste(sort(c(gene_x, gene_y)), collapse = "_")) %>%
 group_by(grp) %>%
 slice(1) %>%
 ungroup() %>%
 select(-grp)