List reformating in R -

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• split comma-separated column separate rows 4 answers

i have df:

   keggnumber         cor             colors x1 c00095            -2.623973e-01    red x2 c17714, c00044    -2.241113e-01    red x3 c00033            -3.066684e-01    red 

and format 2 column dataframe each individual keggnumber matched color. this:

keggnumber  colors c00095      red c17714      red c00044      red c00033      red 

essentially, new dataframe take rows of old dataframe more 1 keggnumber , splits them up, while keeping same color each.

tidyr makes quite easy:

library(tidyr)  df %>% separate_rows(keggnumber) ##          cor colors keggnumber ## 1 -0.2623973    red     c00095 ## 2 -0.2241113    red     c17714 ## 3 -0.2241113    red     c00044 ## 4 -0.3066684    red     c00033 

chop off cor column if like.

a less-pretty base option:

do.call(rbind,          map(function(x, y){data.frame(keggnumber = x, colors = y)},              strsplit(as.character(df$keggnumber), ', '),              df$colors)) ##   keggnumber colors ## 1     c00095    red ## 2     c17714    red ## 3     c00044    red ## 4     c00033    red