Merge multiple rows with some similar column values

Question

       ax  ay  az  bx  by  bz cx cy cz dx dy dz ex ey ez Hid       PX       PY       PZ
1   330 295 998   0   0   0  0  0  0  0  0  0  0  0  0   0 279.6626 310.3374 923.4111
2     0   0   0 260 375 941  0  0  0  0  0  0  0  0  0   0 279.6626 310.3374 923.4111
3     0   0   0 245 375 949  0  0  0  0  0  0  0  0  0   0 279.6667 310.2424 924.7394
4   330 295 998   0   0   0  0  0  0  0  0  0  0  0  0   0 279.6667 310.2424 924.7394

For same PX,PY and PZ values I want to merge the rows for eg the output should be

    ax  ay  az  bx  by  bz cx cy cz dx dy dz ex ey ez Hid       PX       PY       PZ
1   330 295 998 260 375 941   0  0  0  0  0  0  0  0  0   0 279.6626 310.3374 923.4111
2   330 295 998 245 375 949  0  0  0  0  0  0  0  0  0   0 279.6667 310.2424 924.7394

you don't say anything about the output you want but jour could take a look at join() from the dplyr package https://stat545-ubc.github.io/bit001_dplyr-cheatsheet.html — MLavoie, Jan 13 '16 at 12:35
See also: http://stackoverflow.com/questions/9723208/aggregate-multiple-variables-simultaneously — Jaap, Jan 13 '16 at 12:39

score 3 · Answer 1 · answered Jan 13 '16 at 12:37

3

With data.table, you can try this (your data.frame being called df):

library(data.table)
setDT(df)[, lapply(.SD, max), by=.(PX, PY, PZ)]
#         PX       PY       PZ  ax  ay  az  bx  by  bz cx cy cz dx dy dz ex ey ez Hid
#1: 279.6626 310.3374 923.4111 330 295 998 260 375 941  0  0  0  0  0  0  0  0  0   0
#2: 279.6667 310.2424 924.7394 330 295 998 245 375 949  0  0  0  0  0  0  0  0  0   0

answered Jan 13 '16 at 12:37

Cath

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Hey This is not working correctly – user459 Jan 13 '16 at 14:54
1

@HimaanshuGauba could you be more specific ? it works with the example data. If it's because of the columns reordering, you can change that. – Cath Jan 13 '16 at 15:00

Merge multiple rows with some similar column values

1 Answers1