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: funSmoothStrainQuadtree.m
    path of file: ./repos/2D_ALDIC/func_quadtree
    
    the code of the file until where you have to start completion: function F = funSmoothStrainQuadtree(F,DICmesh,DICpara)
%FUNSMOOTHSTRAINQUADTREE: to smooth solved strain fields by curvature regularization
% 	F = funSmoothStrainQuadtree(F,DICmesh,DICpara)
% ----------------------------------------------
%
%   INPUT: F                 Deformation gradient tensor: 
%                            F = [F11_node1, F21_node1, F12_node1, F22_node1, ... , F11_nodeN, F21_nodeN, F12_nodeN, F22_nodeN]';
%          DICmesh           DIC mesh
%          DICpara           DIC parameters
%
%   OUTPUT: F                Smoothed strain fields by curvature regularization

    
function F = funSmoothStrainQuadtree(F,DICmesh,DICpara)
%FUNSMOOTHSTRAINQUADTREE: to smooth solved strain fields by curvature regularization
% 	F = funSmoothStrainQuadtree(F,DICmesh,DICpara)
% ----------------------------------------------
%
%   INPUT: F                 Deformation gradient tensor: 
%                            F = [F11_node1, F21_node1, F12_node1, F22_node1, ... , F11_nodeN, F21_nodeN, F12_nodeN, F22_nodeN]';
%          DICmesh           DIC mesh
%          DICpara           DIC parameters
%
%   OUTPUT: F                Smoothed strain fields by curvature regularization
%
% ----------------------------------------------
% Reference
% [1] RegularizeNd. Matlab File Exchange open source. 
% https://www.mathworks.com/matlabcentral/fileexchange/61436-regularizend