<p>So here is the fault !  MyFunction::Gradient()  is not defined properly  in  <a href="https://github.com/ranjan1990/mlpack_optimization/blob/master/find_equ.cpp">https://github.com/ranjan1990/mlpack_optimization/blob/master/find_equ.cpp</a> . <br>
The 'i' parameter to the Gradient() method indicates which of the functions, the gradient is being taken for.</p>

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