preprocessing

[J.M. Schoffelen]

Hi Ali,

1 Please make sure you are running the latest fieldtrip-version on
/home/common/matlab/fieldtrip,
2 Read the documentation of preprocessing and read_fcdc_data:

-If your trial collection has been a pseudocontinuous one, you should add a
field to your configuration which listens to the following name:
   cfg.datatype = 'continuous'
-If your trial collection has not been a (pseudo)continuous one, but
trial-based, the crash is put in on purpose, since several preprocessing
steps such as filter padding, and artifact padding rely on the assumption
that in the data, as it is in the datafile, the samples left and right of
the trial-boundaries are contiguous in time. The extra check that is built
in should make the users more aware of what they are doing.

Yours,

Jan-Mathijs

PS: the change in preprocessing so far only pertains to the fcdc-users, all
other users should be aware of how their data has been collected without the
automatic check. The take home message is: beware when you start padding
(which is automatically done at some places, especially in the
artifact-routines, except when you put the relevant parameters to 0 in your
configuration) when you have a trial based collection.

-----Original Message-----
From: FieldTrip discussion list [mailto:FIELDTRIP at NIC.SURFNET.NL] On Behalf
Of Ali Mazaheri
Sent: Friday, January 28, 2005 12:32 AM
To: FIELDTRIP at NIC.SURFNET.NL
Subject: [FIELDTRIP] preprocessing

Hi,
I am trying to once again preprocess some old data.. but I realize that I
can't, even if I use the EXACT same parameters I used to preprocess only
last month.. what could be the deal ? Once again I must emphasize that
the exact same parameters were working on the same file only a month ago


Here is the error I get :

Error using ==> read_fcdc_data
requested data segment extends over a discontinuous trial boundary

Error in ==> \\bond\home\common\matlab\fieldtrip\artifact_jump.m
On line 137  ==>             dat = read_fcdc_data(cfg.datafile, hdr, trl
(trllop,1), ...

Error in ==> \\bond\home\common\matlab\fieldtrip\rejectartifact.m
On line 224  ==>   eval(sprintf('[cfg, %s] = artifact_%s(cfg);',
cfg.artfctdef.type{type}, cfg.artfctdef.type{type}));

Error in ==> \\bond\home\common\matlab\fieldtrip\preprocessing.m
On line 242  ==> [cfg] = rejectartifact(cfg);

Error in ==> Z:\MEG\20041201\cfgmaker.m
On line 22  ==>     data = preprocessing(cfg);