clusterSingleBatches: warning data batch# only had 0 spikes

[chenchals]

HI:
Why do I get this?

In clusterSingleBatches (line 95)
Undefined function or variable 'W'.

Error in clusterSingleBatches (line 108)
Params = [1 NrankPC Nfilt 0 size(W,1) 0 NchanNear Nchan];
and errors out...
I tried changing ops.trange ... [0 60] or [0 180]
Time 0s. Determining good channels..
found 137044 threshold crossings in 182.63 seconds of data
found 0 bad channels
Time 12s. Computing whitening matrix..
Getting channel whitening matrix...
Channel-whitening filters computed.
Time 22s. Loading raw data and applying filters...
Time 33s. Finished preprocessing 34 batches.
Obtained 7 PC waveforms in 0.34 seconds
Warning: data batch #1 only had 0 spikes

[chenchals]

all 34 batches has 0 spikes...