Mimie - see xlsread for how you can read in the data from the spreadsheet, and in particular, the red and green columns. For your case, you may want to do something like filename = 'microarrayMimie.xls';
firstPair = xlsread(filename,'E:F');
secondPair = xlsread(filename,'H:I')
where you read in two columns at a time, those in E and F, and those in H and I.
Your next step is that you want to compare to one value. Please elaborate - which elements of the columns are you comparing, and to what?
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