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Bug 108 - reading in of ctf-header with headerformat ctf_ds outputs a lot of stuff to the screen, making it slow

Status	CLOSED FIXED
Reported	2010-07-08 16:02:00 +0200
Modified	2010-12-08 11:13:01 +0100
Product:	FieldTrip
Component:	fileio
Version:	unspecified
Hardware:	PC
Operating System:	Mac OS
Importance:	P1 enhancement
Assigned to:	Joint development user
URL:
Tags:
Depends on:
Blocks:
See also:

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Jan-Mathijs Schoffelen - 2010-07-08 16:02:19 +0200

When reading in CTF.res4 header information using the external ctf toolbox, a lot of info is printed to the screen. This considerably slows down the reading. Cause: getCTFBalanceCoefs tries to read the balancing coefficients for the 3order synthetic gradient with adaptive noise cancellation (G3AR) which does not generally exist when not explicitly created by the user. The function outputs a lot of stuff to the screen when it fails to read (and does not throw an error). Easy fix would be to disable the attempt to read in the G3AR coefficients.

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Jan-Mathijs Schoffelen - 2010-07-09 09:13:29 +0200

As a workaround some change has been made to ft_read_header, which avoids going into getCTFBalanceCoefs when balancing coefficients of a particular type are not present. I contacted Marc Lalancette to change this workaround into a more elegant solution by adjusting the low level code. As a consequence of the workaround, no output is printed to the screen anymore, and reading of the header now takes approx 0.4 seconds, rather than 2.5 (on my mac); this is comparable with the 0.3 seconds it takes read_ctf_res4 to read the header.