least square mfile coding

Hello....

I have two data that will need to compare between these two data. It just in array data... not in polynomial.. the data is in microsoft excel. How can I compare these two data by writing coding in mfile? What is the coding?

what is the mfile coding for least square method to compare the two data is fit or not, or to know the percentage fit between two data?

Hope you can help me... thanks...