[FieldTrip] [problem] zero plv

[Shen-Mou Hsu]

Dear Users,

I try to calculate the phase locking values following the tutorial and
encounter a problem.

First, I ran freqanalysis as follows:
        cfg                         = [];
        cfg.channel                 = 'EEG';
        cfg.method                  = 'mtmfft';
        cfg.foi                     = 8:1:120;
        cfg.keeptrials              = 'yes';
        cfg.ouput                   = 'fourier';
        cfg.tapsmofrq               = 2;
        Phase= ft_freqanalysis(cfg, data);

I noticed that the values in both Phase.cumsumcnt and Phase.cumtapcnt are
constant values (BTW, what the meaning of cumsumcnt and cumtapcnt)

Then, I ran connectivity analysis as follows
        cfg                         = [];
        cfg.method                  = 'plv';
        PLV = ft_connectivityanalysis(cfg, Phase);

Here, I got empty matrices in both labelcmb: {0x2 cell} and plvspctrm:
[0x113 double]

I wondered if there is anything wrong with the previous steps. Many thanks!

Shen-Mou Hsu
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