Non-matched waveforms only

[covertg]

Apologies if this isn't the right place to inquire about this. Hopefully an easy question:

I'd like to work with the whole waveforms database, including clinical records for the "matched" subset when possible. I've so far just been working with the matched subset as it exists in its own database. I'd now like to read only the waveforms that were not matched; that is, the set difference {waveforms}\{waveforms matched}. I see that the full waveforms database contains the directories 30,...,39/ and matched/. However, the directories 30,...,39 have a total of 67,830 record sets. That's also the number of record sets stated as total record sets on the physionet database page, which would seem to indicate that those directories contain both non-matched and matched waveforms; i.e., the matched/ directory contains duplicate data.

Is this correct? If so, how can we identify only the non-matched waveform data?

Thanks in advance.

(updated post after looking into the numbers more.)