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Как итеративно получить доступ к каждому элементу таблицы данных в R?

У меня есть мой самый первый опыт работы с таблицами данных. У меня есть таблица данных "dt", созданная с помощью:

dt <- setNames(data.table(matrix(rnorm(10), nrow = 20, ncol = 5)), c("A", 
      "B","C", "D", "E"))


dt>

        A          B          C          D          E
 1: -1.6288978 -1.6288978 -1.6288978 -1.6288978 -1.6288978
 2: -1.7256894 -1.7256894 -1.7256894 -1.7256894 -1.7256894
 3:  0.2317219  0.2317219  0.2317219  0.2317219  0.2317219
 4: -0.1146546 -0.1146546 -0.1146546 -0.1146546 -0.1146546
 5:  0.3017276  0.3017276  0.3017276  0.3017276  0.3017276
 6: -0.9280297 -0.9280297 -0.9280297 -0.9280297 -0.9280297
 7:  1.3672226  1.3672226  1.3672226  1.3672226  1.3672226
 8:  0.7097482  0.7097482  0.7097482  0.7097482  0.7097482
 9: -1.3607799 -1.3607799 -1.3607799 -1.3607799 -1.3607799
10: -0.6886022 -0.6886022 -0.6886022 -0.6886022 -0.6886022



Я хочу итеративно прочитать элементы этой таблицы данных "dt" в первый и второй столбцы пустой таблицы данных "dt1" с 10 строками и двумя столбцами.

dt1 <- setNames(data.table(matrix(NA, nrow = 10, ncol = 2)), c("X", "Y"))

     X  Y
 1: NA NA
 2: NA NA
 3: NA NA
 4: NA NA
 5: NA NA
 6: NA NA
 7: NA NA
 8: NA NA
 9: NA NA
10: NA NA

Like I will do for a data frame, I wrote the following nested for loop to iteratively access elements from data frame dt and put into the relevant columns of "dt1".

But my code generates the following error:

 j (the 2nd argument inside [...]) is a single symbol but column name 'k' is not found. Perhaps you intended DT[, ..k]. This difference to data.frame is deliberate and explained in FAQ 1.1.

I have read through FAQ 1.1. but I am not able to get a clear solution. Can any one give a hint on how to iteratively access each element of of the data table so I can complete the task? Thank you in advance.

What I have tried:

<pre>co <- 2
ro <- 10




for(k in 1:co){  
     for (i in 1:ro) {    
       dt1[i,1]<-dt[i,k]   
       dt1[i,2]<-dt[i,"E"] 
     }
}

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