r - Gather groups of columns -

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• binding columns similar column names in same dataframe in r 5 answers

i have data online survey respondents go through series of 5 questions. data working @ looks this:

    p1 p2 p3 p4 p5  p1 p2 p3 p4 p5  p1 p2 p3 p4 p5     1  2  3  4  5   1  2  3  4  5   1  2  3  4  5     6  7  8  9  10  6  7  8  9  10  6  7  8  9  10 

the desired output is:

     p1 p2 p3 p4 p5        1  2  3  4  5      6  7  8  9  10      1  2  3  4  5      6  7  8  9  10      1  2  3  4  5      6  7  8  9  10 

i have been trying solve problem library tidyr, can't understand how apply it. advise on helpful.

one of solutions can be:

require(foreach) require(dplyr) require(magrittr)      foreach(   unique_name = unique(colnames(df)),   .combine = 'bind_cols' ) %do% {    df[grep(unique_name), colnames(df)] %>%     unlist() %>%     as.data.frame() %>%     set_colnames(., unique_names)  }