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Subject: Nonlinear Curve Fitting
Date: Mon, 24 May 2010 22:20:21 +0000 (UTC)
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Hi All, 

I have searched through the Matlab forums, but haven't found the answer to my question. I would like to use a least squares function to fit some data. 

Briefly, I have two equations of the form

Z1 = a + b*x + c*y + d*x*y 
Z2 = e + f*x + g*y + h*x*y

where i know Z1, Z2, x, and y and they're in vector form. I have a few hundred data points, so the lack of data is not an issue. Is there a way I can use the lsqcurvefit function to figure out a thru h or is this a more complex problem?