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rsubsetsamplesampling

How does this code of R means?

The first line import the data file and the second one suppose to create a subset of 100 data

i) Assign the data to a matrix, e.g. using

the.data <- as.matrix(read.table("filename.txt"))

(ii) Your variable of interest is Y-Rank ID.Generate a subset of 100 data, e.g. using:

**my.data <- the.data[sample(1:161,100), c(1,3:10,12,13)]**

What does second line of code means??? thanks

Solution

  • In the following line of code:

    my.data <- the.data[sample(1:161,100), c(1,3:10,12,13)]

    The first index into my.data corresponds to the desired rows, and the second index corresponds to the desired columns.

    sample(1:161,100)     <-- take 100 random rows from 1 to 161
c(1,3:10,12,13)       <-- take columns 1, 3 to 10, 12, and 13