mycsg SASnR2 2810_Replicating_usage_of_loops_for_dummy_creation

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Replicating the concept of usage of loops for dummy data creation

Lesson Description

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Sometimes, we want to work with the concept of "Replicating the concept of usage of loops for dummy data creation" in a clear, repeatable way.
This lesson walks through a simple example and shows the key steps.
We will see one approach on how we can do it in SAS and R.

SAS (Base SAS)

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data loop;
    do treatment=1,3,5;
        do avisitn=0,1,2,8;
            output;
        end;
    end;
run;

R (tidyverse)

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library(tidyverse)

 

loop <- crossing(treatment = c(1, 3, 5), avisitn = c(0, 1, 2, 8))

R (base)

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loop <- expand.grid(
  treatment = c(1, 3, 5),
  avisitn = c(0, 1, 2, 8)
)

expand.grid() creates all combinations of treatment and visit values.