Simon Sayz tagasimon

Why is NA == NA = NA? Most Objects in R compared to themselves return TRUE but no NA. It’s actually i had never thought about but thinking about it makes some alot of sense, Comparing two Unknowns shouldn’t be return TRUE. Let’s Look at some of the Most Common examples that return TRUE 10 == 10 ## [1] TRUE -10 == -10 ## [1] TRUE FALSE == FALSE ## [1] TRUE "NA" == "NA" ## [1] TRUE This is a string “NA” and not the NA we are talking about and will return a TRUE just like any other similar string comparison

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