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Bug 1622 - ft_fetch_data always gives error when trials overlap in data

Reported 2012-08-01 15:07:00 +0200
Modified 2013-01-17 10:40:35 +0100
Product: FieldTrip
Component: core
Version: unspecified
Hardware: PC
Operating System: Windows
Importance: P3 normal
Assigned to: Roemer van der Meij
Depends on:
See also:

Roemer van der Meij - 2012-08-01 15:07:53 +0200

Jan-Mathijs Schoffelen - 2012-08-01 15:11:15 +0200

this is appropriate behavior, isn't it? Otherwise it's ambiguous as to from which trial to select the requested samples.

Roemer van der Meij - 2012-08-01 15:13:20 +0200

For now, I added a keyvalue-pair (allowoverlap = true) to fetch_data to escape the error for use in ft_databrowser. The need for this arose in databrowser, where there are overlapping trials and cfg.continous = 'yes'. When zoomed out enough, the requested data is present in several trials. In effect, the samples requested are taken from the last trial where they occur. The only issue I see with allowing overlapping trials in fetch_data is filter-ringing or other preprocessing steps that can affect each sample in a trial differently.

Roemer van der Meij - 2012-08-01 15:18:15 +0200

Ah, wrote the comment in the mean-time. I saw two options: 1) knock out overlapping trials when data was handed as input (it should work fine when read in from disk). This creates different behavior for data on disk vs already read-in. 2) allow it for data that is already read-in. I have a slight preference for the last as it is cleaner coding, but smudgier data-handling. But since it is only for browsing, that was okay in my opinion. But not a very strong preference (the error was just in the way).

Roemer van der Meij - 2012-08-02 15:44:14 +0200

I'll change it to a warning when the exception is used, that should be good enough until someone complains :)

Roemer van der Meij - 2012-08-02 15:48:12 +0200

Changed to 'fixed'

Roemer van der Meij - 2013-01-17 10:40:35 +0100

bug closing time