Looping through dataset in R

Question

I have a data frame "MYdata" and want to split this up to create three new datasets "test_1", "test_2" and "test_3". The first one "test_1" should contain only the first column from "MYdata", the second dataset should only contain the second column and so on. I am trying this:

for (i in 1:3)
{
test_[i] <- MYdata[i]
}

But I get the following error message: "Error in test_[i] <- MYdata[i] : object 'test_' not found"

Any ideas?

`[` is for indexing an existing object - not for creating new object names. BTW: you should learn using lists (but then eventually there is no need to construct new objects because a dataframe is a special kind of list). — jogo, Aug 02 '18 at 13:23

score 0 · Accepted Answer · answered Aug 02 '18 at 13:34

0

You can use assign to include a value in an object with name specified by paste0.

for (i in 1:3) {
  assign(paste0("test_", i), MYdata[i])
}

Each column will be a new data frame.

answered Aug 02 '18 at 13:34

Bruno Pinheiro

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1

`library("fortunes"); fortune(236)` https://stackoverflow.com/questions/17559390/why-is-using-assign-bad?s=6|45.4089 – jogo Aug 02 '18 at 13:38
Thanks Bruno. That is exactly what I needed! – SAS_converted_to_R Aug 02 '18 at 13:44
Thanks for your suggestion @jogo. I'm new on R and have learned a lot with this kind of tips. I will need to study this better to really understand. – Bruno Pinheiro Aug 02 '18 at 13:59
@SAS_converted_to_R if the answer is correct, mark it as the answer for the question, please :) – Bruno Pinheiro Aug 21 '18 at 21:55
Sorry this was my first post. I believe I have marked it now. Thanks and sorry again. :) – SAS_converted_to_R Aug 22 '18 at 11:06

Looping through dataset in R

1 Answers1