Dear Monks,

I would like to clean up a file containing some numbers by eliminating duplicates. The numbers are delimited with a new line.

My idea would be to read the file into an array and then write each element (=each number) into a new file unless it has already been processed. To do that, however, I would need to check whether or not a scalar (containing the new number) is identical to an element of an array (containing all numbers already processed). I did not find anything with regard to such a "contained in" function for arrays. Note that this would involve an operation consisting of an array (the checklist) and a scalar (the new number).

Presumably something like this exists (as it is a fundamental concept in mathematics).

Hints would be greatly appreciated!

In reply to Getting rid of duplicates by New Novice

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