如何根据 r 中的数值分隔一列数字？

Question

trying to find the right code to use to try and separate the column of tests into two different columns named Test1 and Test2. I tried using the separate function like so but always get two columns but 'test2' column is just na's.

Tests
1
1
2
2
1
2
1
2
1

code used
separate(Tests, c('test1', 'test2'))

i want it to look like this. Not sure if i have the wrong function of if i have to add something else into the function to get the column to separate how i want it to. Any advice would help :) thank you!

test1  test2
1       2
1       2
1       2
1       2
1       2

Answer 1

I am supposing that your Tests is a simple vector (guess they are tecnically called atomic vectors but I could be wrong):

 Tests <- c(1,1,2,2,1,2,1,2,1)

You could just filter according to the condition and bind the result into a new data.frame (if Tests is a data.frame with on column called "Tests" just put a "," before each "]":

 as.data.frame(cbind(Test1 = Tests[Tests == 1],  Test2 = Tests[Tests == 2]))

But as you will see R gives you a warning, because there are more 1s than 2s and here comes a very important thing to notice: R will recycle the shorter vector to fill up the data.frame Because in a data.frame all columns have to be of the same length!

So what you are looking to do is dangerous as you most probably can not be sure that everything will have the same length. Possibly the recycling is not desired behaviour so be aware of that.