you mean +[0;0;0], and -[0;0;0] ?
On 30 May 2008, at 17:07, Bruce Fischl wrote:
> p.p.s. in general you have to sample in both directions I think
> On Fri, 30 May 2008, Tim Behrens wrote:
>
>> if bval =0, bvec can be anything (as it will be multiplied by 0!),
>> but it has to be there.
>>
>> T
>> On 30 May 2008, at 16:01, Erik O Hanlon wrote:
>>
>>> Hello Ted,
>>> Thanks for the quick response. Much appreciated. I have 16 values
>>> in my bvec file as you say but I thought that when normalized the
>>> sum of the X Y and Z values had to be 1. Does this mean that the
>>> bvec entries that match the bval of 0 (in my case the first
>>> value in the x,y and z rows) don't have to sum to one?
>>> Thanks again for your reply
>>> best
>>> Erik
>>> On 30/05/2008, Ted Yanagihara <[log in to unmask]> wrote:
>>> On May 30, 2008, at 10:35 AM, <ERIK> <O'Hanlon> <[log in to unmask]>
>>> wrote:
>>> Hello Fsl experts,
>>> Just wondering if somone could clear up the format of the bvec
>>> and bval
>>> files. In the bval file I have 1 b0 and 15 b800 values, my bvec
>>> file has
>>> sixteen entries for x y and Z. Should there be zeros in the bvec
>>> file
>>> where the b0 entry is?
>>> Yes
>>> My b0 value comes first so does this mean that the
>>> first entry in the bvec file should be x= 0 y= 0 and z=0. What
>>> will the
>>> effect be if these values are non zero.
>>> The analysis wont run because there will be 16 entries in bvals
>>> and 15 in bvecs. Don't forget to run dtifit and check the
>>> orientations of V1 (before running bedpost).
>>> good luck!
>>> ted
>>> Thanks for any help you can offer.
>>> best
>>> Erik
>>> --
>>> Erik O'Hanlon
>>> School of Psychology and Institute of Neuroscience,
>>> 3r.d Floor Rm. 3.23,
>>> The Llyod Institute,
>>> University of Dublin,
>>> Trinity College Dublin,
>>> Dublin 2,
>>> Ireland.
>>> Tel. + 353-1-8964801
>>> Fax. +353-1-896 3183
>>> E-mail: [log in to unmask]
>>
>>
>
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