[FieldTrip] integer frequencies in TFR

[Jose]

dear list,

I'm analysing CTF MEG data (sampling rate 1250 Hz).
I'm epoching my data from -0.5 sec to 2.8 sec relative my marker of
interest.

% define the trial matrix
trlFile = zeros(length(markers3), 3);
for i_trial = 1:length(markers3)
    trlFile(i_trial,1) = markers3(i_trial,2) -625; % 0.5*1250 % SR = 1250,
    trlFile(i_trial,2) = markers3(i_trial,2) +3500; % 2.8*1250 % SR = 1250,
    trlFile(i_trial,3) = -625;
    trlFile(i_trial,4) = markers3(i_trial,1);
end

Once I pre-process the data, I run TF analyses with the wavelet method

cfg = [ ];
cfg.trials = find(data2.trialinfo(:,1) == i_condition);
cfg.channel = 'MEG';
cfg.method = 'wavelet';
cfg.width = 5;
cfg.output = 'pow';
cfg.foi = 1:1:30;
cfg.toi = -0.5:0.05:2.8;
TFdata = ft_freqanalysis(cfg, data1);

In the .freq field I realize that my frequency are not exact integers

0.907801418439716    2.11820330969267    3.02600472813239
3.93380614657210    5.14420803782506    6.05200945626478
6.95981087470449    7.86761229314421    9.07801418439716
9.98581560283688 ...

I checked:
http://www.fieldtriptoolbox.org/faq/why_am_i_not_getting_exact_integer_frequencies

So, I decide to reduce one sample in my trial definition (so
trlFile(i_trial,2) = markers3(i_trial,2) +3500-1; % 2.8*1250 % SR = 1250,)

But, still I'm not having integers,

0.909090909090909    2.12121212121212    3.03030303030303
3.93939393939394    5.15151515151515    6.06060606060606
6.96969696969697    7.87878787878788    9.09090909090909    10 ...

I suspect I can't obtain integer frequencies in my TFR due to my frequency
sampling,
Is there any recommendation regarding the frequencies used to compute the
TFRs?
Would that pose some issues for subsequent processing steps?

thanks
Jose
<https://sites.google.com/site/joseluisulloafulgeri/>
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