Alex
Uu is an n x 3 matrix. n will be the number of causes or inputs. So
for example if you had attention and no attention conditions n would
be 2.
Uu only contains numbers, not text.
The first column indexes SPM.Sess.U and would correspond to i as in
SPM.Sess.U(i).
The second column indexes the name of the input or cause, and would
correspond to j in SPM.Sess.U(i).name{j}. The second column will
generally be 1 unless there are parametric effects.
The third column is the contrast weight.
Uu is not a cell array and is not a structure, just a matrix.
Darren
On Wed, Nov 4, 2009 at 12:40 PM, Alex Fornito <[log in to unmask]> wrote:
> Hi all,
> I'm trying to understand the structure of the inputs to the spm_peb_ppi
> function. Specifically, I'm trying to get a handle on what's contained in Uu
> (is it supposed to be a matrix or a cell structure?).
>
> Assume I have one task regressor called 'condition' and the contrast weight
> is 1.
> I'm assuming the following
>
> Uu{1,2} = 'condition'
> Uu{1,3} = 1 (i.e., just a single entry of 1).
>
> Does
> Uu{1,1}= SPM.Sess(1).U(1).u, or something else?
>
> A concrete example would be much appreciated.
> Many thanks,
> Alex
>
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