Hi,
The answer is no.
It is complicated by the fact that the centre of rotation is not at
(0,0,0)
and hence the translation component of the matrix is a combination
of the translations in the parameters and effectively induced
translations
from the rotations. Best not to worry about this as you don't need to
know
in order to use the tools effectively.
All the best,
Mark
On 29 Sep 2010, at 23:20, vivian wrote:
> Hi Mark,
>
> May I ask if the line is Rx, Ry, Rz, Tx, Ty, Tz, should the last
> three components of the line be 0.533133, 0.187519, -2.275521 as
> given by the matrix?
>
>
> On Thu, Sep 30, 2010 at 12:16 AM, Mark Jenkinson
> <[log in to unmask]> wrote:
> Dear Leo,
>
> There is a mapping between the par and the mat files but it
> is not simple and unless you *really* need to know then I
> would advise not bothering with it.
>
> To regress out motion the simple thing to do is to use the
> parameters (from the .par file) directly as regressors.
> This is most easily done in FEAT using the GUI (there is
> a single button) but you can import the .par file as columns
> in a design matrix in any other GLM too.
>
> As to your last question, the parameters are:
> Rx Ry Rz Tx Ty Tz
> where R is a rotation (angle in radians) and T is
> a translation (in mm).
>
> All the best,
> Mark
>
>
>
> On 29 Sep 2010, at 17:59, Yiou Li wrote:
>
> Hi,
>
> I checked the history threads and Couldn't find the following question
> about McFlirt being addressed.
>
> Could any expert on McFlirt/Flirt kindly advise?
>
> Best,
> Leo
>
>
> ---------- Forwarded message ----------
> From: Yiou Li <[log in to unmask]>
> Date: Tue, Sep 28, 2010 at 3:42 PM
> Subject: Question about MCFLIRT output transformation
> To: FSL - FMRIB's Software Library <[log in to unmask]>
>
>
> Hi all,
>
> I performed a 6 DOF of mcflirt on a function MRI dataset and asked for
> output transformation as well as the parameters (i.e., -mats and
> -plots are both used).
>
> I checked the first line of the .par file:
>
> -0.0198375 -0.00176798 -0.0073474 -0.0507674 -0.458798 -0.553456
>
> and the first mat file (MAT_0000)
>
> 0.999971 -0.007347 0.001768 0.533133
> 0.007381 0.999776 -0.019836 0.187519
> -0.001622 0.019849 0.999802 -2.275521
> 0.000000 0.000000 0.000000 1.000000
>
> The questions are:
> 1. Is there is correpsondence between the lines of .par and the MAT
> data? If so, how is the mapping?
>
> 2. To regress out the motion effects, should the lines of .par be used
> and what are the specific meanings of each column? (e.g., rotation,
> translation etc.)
>
> Your input is appreciate!
> Leo
>
>
>
>
> --
> Xiaowei.Zou
>
> Department of Biomedical Engineering
> Columbia University
> New York, NY, 10027
>
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