importing .eeg data files

[Robert Oostenveld]

Hi Maria,

On 12 Nov 2004, at 11:13, Maria Stavrinou wrote:

> I am trying to import .eeg datafile from Neuroscan using the command
> read_fcdc_data in this sense:
>   dat = read_fcdc_data('dataset_test.eeg', hdr, 1,
> number_of_trials*number_of_points_in_one_trial*num_channels, chanindx)
> However i would like to import all 62 channels -could you give me also
> a hint what to write to chanindx?
> and the answer i get is:
>
> Error using ==> read_fcdc_data
> cannot read beyond epoch boundary in Neuroscan *.eeg file

The error is not with chanindx, but with the fact that you are trying
to read a very long continuous block of data from a file that contains
only epochs. It cannot read data beyond the boundaries between the
epochs.

In principle you should not be using the read_fcdc_data function to get
the data into Fieldtrip, since it is a low-level function. You should
use the "preprocessing" function. See "help preprocessing" and "help
definetrial". Probably the following configuration will do the trick

cfg = []
cfg.datafile   = 'dataset_test.eeg'
cfg.headerfile = 'dataset_test.eeg'
cfg.channel = 'all'
raw = preprocessing(cfg)

I hope this helps,
Robert