Hello Alfonso -

I based a MATLAB script on what you wrote. However, it is giving me an error. Could you please help me:

clear batch;
batch.Setup.subjects.effect_names{1}='Active';
batch.Setup.subjects.effects{1}=full(sparse(group_Active,1,1,numel(group_Active)+numel(group_SHAM),1));
batch.Setup.subjects.effect_names{2}='SHAM';
batch.Setup.subjects.effects{2}=full(sparse(group_SHAM,1,1,numel(group_Active)+numel(group_SHAM),1));
for n1=1:numel(group_Active)
batch.Setup.subjects.effect_names{2+n1}=['Subject',num2str(n1,'%02d')];
batch.Setup.subjects.effects{2+n1}=full(sparse([group_Active(n1),group_SHAM(n1)],1,1,numel(group_Active)+numel(group_SHAM),1));
end

conn_batch(batch);

I have 2 groups Active vs Sham

The error is : Error using sparse
Index exceeds matrix dimensions.

Can you please help me.

thank you,

Jake