Are you using the temporal concatenation approach? What is the voxel
resolution of your volumes?
The 'std::bad_alloc' error typically means that melodic has run out of memory.
With 64 GB of RAM, this should not happen for a single subject with 500
volumes at a resonable resolution (i.e. 4 mm voxel). However, if you are doing
temporal concatenation on many subjects (i.e. more than 20) or if your voxel
resolution is high (i.e. 1mm or 2mm), then memory could indeed be an issue.
I would not expect the fact that your data has been spatially smoothed to
cause this sort of problem. You can always try running melodic on unsmoothed
data if you suspect this is the issue.
On Tuesday, February 14, 2012 11:52:11 you wrote:
> Dear all,
>
> Thank you for your helpful suggestions so far. I have now tried the
> following two ways of running MELODIC on a Ubuntu Linux system
> (2.6.31-23-server, x86_64) with 64 GB of memory.
>
> (1) I entered the smoothed 4D data (500 volumes) in the Melodic GUI,
> defined all required settings on the Data tab, and deselected all other
> preprocessing steps on the Pre-Stats and Registration tabs. I did this for
> all subjects. Some subjects seemed to be running but nothing happened. For
> others I received the following error message: 'terminate called after
> throwing an instance of 'std::bad_alloc''.
>
> (2) I next tried to run Melodic from the command line, using: melodic -I
> swfmri.nii -o swfmri_mel -nobet -nomask -report -tr=2.5. Using this
> command worked for one subject while all others failed with the following
> error message: 'terminate called after throwing an instance of
> ‘std::bad_alloc’ what(): std::bad_alloc Aborted'.
>
> Has anyone experienced this problem before? What other information could I
> provide to help find a solution?
>
> Best,
> Sandra
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