如何根据行号对r中的行进行分组

Question

I would like to make 2 groups based on their row numbers (the 1st group being rows 2 to 47, and the 2nd group being rows 48 to 92). The groups are my top and bottom performing samples and I would like to compare the groups' values in the 12 data columns (genes being tested). So, my ultimate goal is to divide the samples into their appropriate groups, and run statistical analyses the group's values for each of the genes tested. Here is a small section of my table:

Sample    icaA   icaB   icaC   icaD
ST1       12     13     15     18
ST2       11     9      8      16
ST3       15     18     18     15
ST4       13     16     17     20

I don't know if I can use cbind to combine the groups. I think I've also seen others flip the rows and columns; I can do that if needed. I'm just a beginner with the software, so any suggestions would be great!

Answer 1

To get the first group:

df1 <- df[2:47, ]

To get the second group:

df2 <- df[48:92, ]

Right?

Then you can run stats on each column, for instance, like this:

apply(df1[-1], 2, mean)

...To get the mean for each column, in the first group.

Then for the mean of each column in the second group:

apply(df2[-1], 2, mean)

Then to bind each group into 1 dataframe (or matrix) again, then I recommend:

rbind(df1, df2)