Double loop to create a dataframe

[LasiaR]

Hello !
I am a newbie on R and i am face a problem that i hope someone here can help me ^^

I have several .txt document whose i want to study

I import and create several data frame for each document

folder <- "/Users/sylvain/Desktop/php/linking-interne-semantique/"      # path to folder that holds multiple .csv files
files_names3 <- list.files(path="/Users/sylvain/Desktop/php/linking-interne-semantique", pattern="*.txt")

for (i in 1:length(files_names3)){
  assign(files_names3[i],
         read.delim(files_names3[i])
  )}

I have in total, 33 documents, now i want to create a data frame, which each document will be compare each other.

Example : i have, " doc1.txt ", " doc2.txt ", "doc3.txt"

i need a result similar to :
doc1.txt doc1.txt
doc1.txt doc2.txt
doc1.txt doc3.txt
doc2.txt doc1.txt
doc2.txt doc2.txt
doc2.txt doc3.txt
doc3.txt doc1.txt
doc3.txt doc2.txt
doc3.txt doc3.txt

I have this code :

for (i in 1:length(files_names3)) {
  for (j in 1:length(files_names3)) {
   print(paste(files_names3[i],files_names3[j],sep=","))
  }
}

When i print, it works, but i dont know how to set the whole resultat to a dataframe

Any help ?

Thx !!!!

[Yarnabrina]

Welcome to the community!

I'm not sure, but is this what you want?

file_names <- c("doc1.txt ", "doc2.txt ", "doc3.txt")
df <- expand.grid(file_names, file_names)
df
#>        Var1      Var2
#> 1 doc1.txt  doc1.txt 
#> 2 doc2.txt  doc1.txt 
#> 3  doc3.txt doc1.txt 
#> 4 doc1.txt  doc2.txt 
#> 5 doc2.txt  doc2.txt 
#> 6  doc3.txt doc2.txt 
#> 7 doc1.txt   doc3.txt
#> 8 doc2.txt   doc3.txt
#> 9  doc3.txt  doc3.txt

^{Created on 2019-03-25 by the reprex package (v0.2.1)}

[LasiaR]

LOL,

This is exactly what i want !

I tried with expand.grid but it doesn't work :s

I have this response : "Error in View : arguments imply differing number of rows: 1, 33"

You know why ?

[Yarnabrina]

It's hard to say without looking at your exact code.

Can you please turn this into a REPRoducible EXample of your problem?

In case you don't know how to make a reprex, here's a great link:

FAQ: How to do a minimal reproducible example ( reprex ) for beginners

A minimal reproducible example consists of the following items: A minimal dataset, necessary to reproduce the issue The minimal runnable code necessary to reproduce the issue, which can be run on the given dataset, and including the necessary information on the used packages. Let's quickly go over each one of these with examples: Minimal Dataset (Sample Data) You need to provide a data frame that is small enough to be (reasonably) pasted on a post, but big enough to reproduce your issue. Let's say, as an example, that you are working with the iris data frame head(iris) #> Sepal.Length Sepal.Width Petal.Length Petal.Width Species #> 1 5.1 3.5 1.4 0.…

[LasiaR]

thx so much for your help

I found the problem , i had to add " df " on expand.grid !
And have something like :
-> expand.grid.df(doc2,doc2)

^^

But, i am still curious to try to do it with loop, in php, we can do it and it works, but not in R, it weird,
don't you think ?

The whole code :

#preface : i have several .txt document on a folder 
#I need to create a data frame for each document .txt 

folder <- "/Users/sylvain/Desktop/php/linking-interne-semantique/"      # path to folder that holds multiple .csv files
files_names3 <- list.files(path="/Users/sylvain/Desktop/php/linking-interne-semantique", pattern="*.txt")

for (i in 1:length(files_names3)){
  assign(files_names3[i],
         read.delim(files_names3[i])
  )}


# Now about the loop 
#When i print it, it works ! i have the same result as expand.grid. 

for (i in 1:length(files_names3)) {
  for (j in 1:length(files_names3)) {
   print(paste(files_names3[i],files_names3[j],sep=","))
}
}


#So i tried now to put all of that on a data frame, in order to have something like (if i have 3 documents) :  
doc1.txt doc1.txt
doc1.txt doc2.txt
doc1.txt doc3.txt
doc2.txt doc1.txt
doc2.txt doc2.txt
doc2.txt doc3.txt
doc3.txt doc1.txt
doc3.txt doc2.txt
doc3.txt doc3.txt

data <- ''

for (i in 1:length(files_names3)) {
  for (j in 1:length(files_names3)) {
     for (k in 1:9) {
   data[k] <- print(paste(files_names3[i],files_names3[j],sep=","))
}
}
}

I have as result : 

doc 1 doc 1
doc 1 doc 1
doc 1 doc 1
doc 1 doc 1

etc.

[Yarnabrina]

This is not a reprex. Please go through the link I shared earlier. Also, please format your code while posting.

@LasiaR

But, i am still curious to try to do it with loop, in php, we can do it and it works, but not in R, it weird,
don't you think ?

You can create the data frame via for loops, but I guess you'll have to do it via matrix. The reason your code fails is that you are printing the output of paste, instead of storing it. Also, data <- '' is a wrong thing to do.

The following works.

file_names <- c("doc1.txt ", "doc2.txt ", "doc3.txt")

df1 <- expand.grid(file_names, file_names)
df1
#>        Var1      Var2
#> 1 doc1.txt  doc1.txt 
#> 2 doc2.txt  doc1.txt 
#> 3  doc3.txt doc1.txt 
#> 4 doc1.txt  doc2.txt 
#> 5 doc2.txt  doc2.txt 
#> 6  doc3.txt doc2.txt 
#> 7 doc1.txt   doc3.txt
#> 8 doc2.txt   doc3.txt
#> 9  doc3.txt  doc3.txt

df2 <- matrix(ncol = 2,
              nrow = (length(x = file_names) ^ 2))

for(i in seq_along(along.with = file_names))
{
  for(j in seq_along(along.with = file_names))
  {
    df2[(((i - 1) * length(x = file_names)) + j), ] <- c(file_names[i], file_names[j])
  }
}

df2 <- as.data.frame(x = df2)
df2
#>          V1        V2
#> 1 doc1.txt  doc1.txt 
#> 2 doc1.txt  doc2.txt 
#> 3 doc1.txt   doc3.txt
#> 4 doc2.txt  doc1.txt 
#> 5 doc2.txt  doc2.txt 
#> 6 doc2.txt   doc3.txt
#> 7  doc3.txt doc1.txt 
#> 8  doc3.txt doc2.txt 
#> 9  doc3.txt  doc3.txt

^{Created on 2019-03-25 by the reprex package (v0.2.1)}

[LasiaR]

Done I edited sorry !
Thx for your help !!