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How can I combine multiple column values ​​into one column?

I have a data frame called "stemmoutput" (see below):

     X1      X2       X3      X4      X5      X6      X7     X8     X9    X10     
1  tanaman  cabai                                    
2  banget   hama     sakit   tanaman                            
3  koramil  nogosari melaks  ecek     hama   tanaman padi    ppl    ds   rambun

And I want to concatenate multiple column values ​​into one column like this:

     TEXT
1  tanaman cabai                                     
2  banget hama sakit tanaman                            
3  koramil nogosari melaks ecek hama tanaman padi ppl ds rambun

I tried this code and it works

stemmoutput$TEXT <- with(stemmoutput, paste(X1,X2,X3,X4,X5,X6,X7,X8,X9,X10, sep=" "))

but is there any other way that is more efficient, without having to write down the column name one by one?

I also tried this code as shown below but that didn't work either.

for(i in names(stemmoutput)){
     stemmoutput$TEXT <- with(stemmoutput, paste(i, sep=" "))}
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2 answers


Try do.call 

library(stringr)
newdat <- data.frame(TEXT=str_trim(do.call(paste, stemmoutput)),
                     stringsAsFactors=FALSE)

newdat
#                                                         TEXT
#1                                                tanaman cabai
#2                                    banget hama sakit tanaman
#3 koramil nogosari melaks ecek hama tanaman padi ppl ds rambun


Better to use ,

as a separator if the column

there are multipart words 
 TEXT <- gsub(', [^A-Za-z]+', '', do.call(paste, c(stemmoutput, sep=', ')))

 newdat <- data.frame(TEXT, stringsAsFactors=FALSE)
 newdat
 #                                                                  TEXT
 #1                                                        tanaman, cabai
 #2                                          banget, hama, sakit, tanaman
 #3 koramil, nogosari, melaks, ecek, hama, tanaman, padi, ppl, ds, rambun
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Here's another idea using tidyr

If you unite

only want to use columns from X1

to X10

:

library(tidyr)
unite(stemmoutput, TEXT, num_range("X", 1:10), sep = " ")

If you want to concatenate all columns, follow these steps:

unite(stemmoutput, TEXT, everything(), sep = " ")


Benchmarks

I tried two approaches to the reference because I suspected it unite

would be much faster than do.call

that, but they turned out to be pretty equivalent:

df <- data.frame(replicate(10,sample(paste0(
  sample(LETTERS[1:10]), collapse = ""), 10e5, replace = TRUE)))

mbm <- microbenchmark(
  akrun = data.frame(TEXT=str_trim(do.call(paste, df)), stringsAsFactors=FALSE),
  steven = unite(df, TEXT, everything(), sep = " "),
  times = 50
)

enter image description here

# Unit: milliseconds
#    expr       min        lq      mean    median       uq       max neval cld
#   akrun 1117.1350 1132.3861 1146.3943 1136.3094 1145.076 1232.5633    50   b
#  steven  910.7432  924.0386  927.8614  927.7224  929.649  995.3584    50  a
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