How can I append multiple texts to one dataframe (tibble) within a for loop using append function in R?

Question

I have multiple *.txt files that contain the title and texts that I want to process in R. A program below reads all the *.txt and displays the final file while skipping the first read texts. My program is as here below. It uses for loop and I want to see all the texts

library(here)
library(glue)
library(tm)
library(SnowballC)
library(tidyverse)
library(tidytext)

all_texts <- list.files(setwd('.KCI/'), (startsWith = 'abstract'))
for(i in seq(1:length(all_texts)))
{
    data <- read_tsv(all_texts[i], , show_col_types = FALSE)
    corpus <- Corpus(VectorSource(data[i]))
    corpus[i] <- tm_map(corpus[i], tolower)
    corpus[i] <- tm_map(corpus[i], removePunctuation)
    corpus[i] <- tm_map(corpus[i], removeNumbers)
    corpus[i] <- tm_map(corpus[i], stripWhitespace)
    corpus[i] <- tm_map(corpus[i], removeWords, c(stopwords("english"), mystopwords))
    corpus[i] <- tm_map(corpus[i], stemDocument)
    dtm <- DocumentTermMatrix(corpus[i])
  }

This program just reads the final document but skips the previous ones. Therefore I want even other documents to be displayed before the last one.

<Title>       <Year>        <Text>
How is it?     1998          I am wondering if it could end like that. Therefore the deal is too good to be true

Answer 1

This would be a lot easier if you had provided some data.

library(tm)
library(SnowballC)
##
#   two documents based on your example (t1 & t2 are identical here).
#
t1 <- read.delim(text='
                 Title\tYear\tText
                 How is it?\t1998\tI am wondering if it could end like that. Therefore the deal is too good to be true',
                 header=TRUE)
t2 <- read.delim(text='
                 Title\tYear\tText
                 How is it?\t1998\tI am wondering if it could end like that. Therefore the deal is too good to be true',
                 header=TRUE)
data <- list(t1,t2)   # listof documents
dtm.list <- lapply(data, function(x) {
  corpus <- Corpus(VectorSource(x))
  corpus <- tm_map(corpus, tolower)
  corpus <- tm_map(corpus, removePunctuation)
  corpus <- tm_map(corpus, removeNumbers)
  corpus <- tm_map(corpus, stripWhitespace)
  corpus <- tm_map(corpus, removeWords, c(stopwords("english")))
  corpus <- tm_map(corpus, stemDocument)
  DocumentTermMatrix(corpus)
})
lapply(dtm.list, inspect)

Note I left out mystopwords because you did not provide any. In your case you could put the read_tsv(...) back into the function and use lapply(...) in the list of file names. Something like:

dtm.list <- lapply(all.texts, function(x) {
  data   <- read_tsv(x)
  corpus <- Corpus(VectorSource(data))
  ...
})

Where ... are the lines of code in my example above.

If your ultimate goal is to analyze word frequency, you might be better off using ?termFreq.