mycsg SASnR (SAS and R)

SAS code

data ENRLMENT;

infile datalines dlm='|' dsd missover;

input STUDY : $6. PT : $4. ICDT_RAW : $11. ENRLDT_RAW : $11. RANDDT_RAW : $11.;

label STUDY ='Study Number' PT ='Subject Identifier' ICDT_RAW ='Informed Consent Date' ENRLDT_RAW ='Enrollment Date' RANDDT_RAW ='Randomization Date';

format ;

datalines4;

CSG001|1001|1/JAN/2010||
CSG001|1002|1/JAN/2010|4/JAN/2010|
CSG001|1003|1/JAN/2010|3/JAN/2010|3/JAN/2010
CSG001|1004|1/JAN/2010|4/JAN/2010|5/JAN/2010
CSG001|1005|15/JAN/2010|1/FEB/2010|5/FEB/2010
CSG001|1006|18/FEB/2010|1/MAR/2010|1/MAR/2010
CSG001|1007|4/APR/2010|14/APR/2010|14/APR/2010
CSG001|1008|20/JUN/2010|26/JUN/2010|27/JUN/2010
;;;;

run;


data enrl01;

    set enrlment;

    array rvars[*] icdt_raw enrldt_raw randdt_raw;

    do i=1 to dim(rvars);

        rvars[i]=translate(rvars[i],' ','/');

    end;

run;

SAS code description

The SAS code snippet above demonstrates how to use an array to process multiple variables in a dataset. In this example, the dataset "enrlment" is being processed, and an array named "rvars" is created to hold the variables "icdt_raw," "enrldt_raw," and "randdt_raw."

A DO loop is then used to iterate through each element of the array. Within the DO loop, the TRANSLATE function is applied to each element of the array using the TRANSLATE(rvars[i],' ','/') syntax. This function replaces any spaces in the variable value with forward slashes ("/"), effectively performing a character replacement operation.

Finally, the modified values are stored back into the respective variables in the "enrl01" dataset using the assignment statement rvars[i]=translate(rvars[i],' ','/').

R code


library(tidyverse)
library(stringr)
library(purrr)

enrlment<-tribble(
~study,~pt,~icdt_raw,~enrldt_raw,~randdt_raw,
"CSG001","1001","1/JAN/2010","","",
"CSG001","1002","1/JAN/2010","4/JAN/2010","",
"CSG001","1003","1/JAN/2010","3/JAN/2010","3/JAN/2010",
"CSG001","1004","1/JAN/2010","4/JAN/2010","5/JAN/2010",
"CSG001","1005","15/JAN/2010","1/FEB/2010","5/FEB/2010",
"CSG001","1006","18/FEB/2010","1/MAR/2010","1/MAR/2010",
"CSG001","1007","4/APR/2010","14/APR/2010","14/APR/2010",
"CSG001","1008","20/JUN/2010","26/JUN/2010","27/JUN/2010",
)

enrl01<-enrlment %>% 
  mutate(across(c(icdt_raw, enrldt_raw, randdt_raw), ~ str_replace_all(., "/", " ")))

R code description

The above R Tidyverse code snippet demonstrates how to use the mutate and across functions to modify multiple variables in a dataset. In this example, the dataset enrlment is being processed.

The across function is used to select multiple variables (icdt_raw, enrldt_raw, randdt_raw) to apply a transformation to. The str_replace_all function is then used within mutate to replace all occurrences of the forward slash ("/") with a space (" ") in the selected variables.

The tilde (~) notation is used to define an anonymous function to be applied to each selected variable. The dot (.) represents the current variable being processed.

Finally, the modified values are stored in the new dataset rl01 using the assignment statement mutate(across(...)).

Arrays-repeat same logic on multiple variables