killUnwantedChannels function results in 'Matrix index is out of range for deletion.' when not reading waveforms

[stinos]

Practically the 'c:<channels>' argument doesn't work in combination with 'noread' because of the unconditional

NEV.Data.Spikes.Waveform(:, NEV.Data.Spikes.Electrode == unWantedChannels(idx)) = [];

line. Suggestion: wrap that one in if ~isempty(NEV.Data.Spikes.Waveform).

[stinos]

There's a similar issue in openNSx: line 955 should be

elseif ~isempty(NSx.Data)

instead of just else to avoid errors from calls on empty Data.