Question

I am checking for duplicate dates in a data set with the following command:

duplicateTest <- duplicated(index(closePricesClean))

The output for this is a “FALSE” for every date not duplicated. So, if closePricesClean has 500 observations, then duplicateTest will return a list of 500 “TRUE” or “FALSE” values. What I’d like instead is to return a single “FALSE” value if the entire vector is “FALSE” or “TRUE” if the list contains even one “TRUE” value.

Do I need to construct an if statement? Or is there a function that I don’t know about?

Answer 1

Use anyDuplicated and check whether or not its result equals zero. This will be faster than using any on the results of duplicated because it will stop as soon as the first TRUE is encountered.

duplicateTest <- anyDuplicated(index(closePricesClean)) != 0