You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: spm_field.m
    path of file: ./repos/spm
    
    the code of the file until where you have to start completion: function varargout = spm_field(varargin)
% A compiled routine for various spatially regularised inverse problems
%__________________________________________________________________________

    
function varargout = spm_field(varargin)
% A compiled routine for various spatially regularised inverse problems
%__________________________________________________________________________
%
% FORMAT v = spm_field(H, g, param)
% v     - the solution (n1*n2*n3*n4, single)
% H     - parameterisation of a Hessian at each voxel
%         (n1*n2*n3*(n4*(n4-1)), single)
%         Because the Hessian is symmetric, elements along the
%         4th dimension are ordered:
%         h(1,1), h(2,2), h(3,3),... h(1,2), h(1,3), ..., h(2,3)...
%         Each vector along the 4th dimension should encode a
%         positive (semi)definite matrix.
% g     - parameterisation of first derivatives (n1*n2*n3*n4, single)
% param - 10 parameters (settings)
%         - [1][2][3] Voxel sizes
%         - [4][5][6] Regularisation settings.
%           - [4] Penalty on absolute values.
%           - [5] Penalty on the `membrane energy'. This penalises
%                 the sum of squares of the gradients of the values.
%           - [6] Penalty on the `bend