A = ExcelData.VFINX;
B = ExcelData.VISVX;
C = ExcelData.VIVAX;
with a cell array
for cac = {A,B,C}
regress( cac{:}, X )
end
or without A, B and C
data = { ExcelData.VFINX, ExcelData.VISVX, ExcelData.VIVAX };
for cac = data
regress( cac{:}, X )
end
or with a struct
SA=struct('A',ExcelData.VFINX,'B',ExcelData.VISVX,'C',ExcelData.VIVAX);
for cac = reshape( fieldnames( SA ), 1, [] )
regress( SA.(cac{:}), X )
end
 
EDIT
I added
- reshape to the struct case to convert the column, which is returned by fieldnames, to a row, which is required by the for-loop.
- {:} to the struct case
to fix a couple of mistakes
