Hi,
have you looked at http://www.fmrib.ox.ac.uk/fsl/fdt/fdt_dtifit.html?
In your case, the bvals entries will be:
0 1000 1000 1000 1000 1000 1000
and the bvecs:
0 1 -1 0 0 1 -1
0 0 0 1 1 1 1
0 1 1 1 -1 0 0
i.e. each direction occupies one column. For each b=0 entry you need a [0 0 0] gradient direction.
Cheers,
Stam
On 10 Jan 2011, at 13:35, Ivan Maximov wrote:
> Dear Colleagues,
>
> Sorry for the newbie's question.
> I would like to understand how to build up the bvecs file from scratch. The info from DFT webpage is still dark for me. Probably,
> someone could help me.
>
> I have bvals as following: 0 1000 1000 1000 1000 1000 1000
> I means one acquisition for 6 directions.
> The gradient directions are:
> 1 0 1
> -1 0 1
> 0 1 1
> 0 1 -1
> 1 1 0
> -1 1 0
>
> How to construct the bvecs?
>
> Thanks very much in advance
> Ivan
>
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