Dear Rhang,
The number of volumes in the merged files is the number of samples that
are stored for each model parameter (theta, phi, f etc) in order to
describe the distribution on that parameter. This is always 50 and does
not depend at all on the number of volumes of data collected.
Heidi
R Huang wrote:
>Dear Tim
>
>I have one question about the number of volumes for merged_thsamples.
>
>Using fslview to check Bedpost output, I found that
>the merged_thsamples always has 50 volumes,
>no matter how many diffusion gradient directions
>applied in diffusion-weighted images.
>(I have compared the merged_thsamples obtained from
>diffusion data of 36 diffusion directions, 60 directions,
>and 81 directions. The diffusion-weighted data were acquired
>from 1.5T Siemens Sonata, b=0/800).
>
>Any comments and suggestions please
>
>rhuang
>
>
--
Dr Heidi Johansen-Berg
Wellcome Trust Training Fellow
Oxford Centre for Functional Magnetic Resonance Imaging of the Brain
John Radcliffe Hospital
Headington
Oxford OX3 9DU
http://www.fmrib.ox.ac.uk/~heidi
Tel: 01865 222782
Fax: 01865 222717
email: [log in to unmask]
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