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Python Set Operations Explained: From Theory to Real-Time Applications

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A  set  in Python is an unordered collection of unique elements. It is useful when storing distinct values and performing operations like union, intersection, or difference. Real-Time Example: Removing Duplicate Customer Emails in a Marketing Campaign Imagine you are working on an email marketing campaign for your company. You have a list of customer emails, but some are duplicated. Using a set , you can remove duplicates efficiently before sending emails. Code Example: # List of customer emails (some duplicates) customer_emails = [ "alice@example.com" , "bob@example.com" , "charlie@example.com" , "alice@example.com" , "david@example.com" , "bob@example.com" ] # Convert list to a set to remove duplicates unique_emails = set (customer_emails) # Convert back to a list (if needed) unique_email_list = list (unique_emails) # Print the unique emails print ( "Unique customer emails:" , unique_email_list) Ou...
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Here is a Quick Way to Know Current Working Directory in R

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If R is not finding the file you are trying to read then it may be looking in the wrong folder/directory. If you are using the graphical interface you can change the working directory from the file menu.

List of Files and Current Working Directory

Related: JOBS in R Language

If you are not sure what files are in the current working directory you can use the dir() command to list the files and the getwd() command to determine the current working directory:
> dir()
[1] "fixedWidth.dat" "simple.csv"     "trees91.csv"    "trees91.wk1"[5] "w1.dat"
> getwd()
[1] "/home/black/write/class/stat/stat383-13F/dat"

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