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
>
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