NSGA-II in MATLAB 源码中文注释（1）

这里用到的源码是从https://cn.mathworks.com/matlabcentral/fileexchange/10429-nsga-ii--a-multi-objective-optimization-algorithm 下载的，网上搜到说这个比较好，看了看挺简洁的，注释也很全面，自己一边看一边把注释都翻译成中文的，分享出来给初学者们一起学习下哈哈。

1.主程序

function nsga_2(pop,gen)

%% function nsga_2(pop,gen)
% is a multi-objective optimization function where the input arguments are 
% pop - Population size
% gen - Total number of generations
% 这是一个多目标优化函数，pop是种群大小，gen是进化代数。
% This functions is based on evolutionary algorithm for finding the optimal
% solution for multiple objective i.e. pareto front for the objectives. 
% Initially enter only the population size and the stoping criteria or
% the total number of generations after which the algorithm will
% automatically stopped. 
%该函数基于多目标进化算法求解最优方案，即多目标的帕累托前沿。
%最初只输入种群规模和终止条件。
% You will be asked to enter the number of objective functions, the number
% of decision variables and the range space for the decision variables.
%你需要输入目标个数和决策变量个数，以及决策变量的空间范围。
% Also you will have to define your own objective funciton by editing the
% evaluate_objective() function. A sample objective function is described
% in evaluate_objective.m. Kindly make sure that the objective function
% which you define match the number of objectives that you have entered as
% well as the number of decision variables that you have entered. The
% decision variable space is continuous for this function, but the
% objective space may or may not be continuous.
%你还需要通过编辑evaluate_objective()函数来定义你自己的目标函数；evaluate_objective.m里定义了一个目标函数的例子。
%请确保你定义的目标函数与你输入的目标个数、决策变量个数相匹配。该函数的决策变量空间是连续的，但是目标空间可以是连续或者离散的。
%另外网上资料说objective_description_function.m 要自己重写
% Original algorithm NSGA-II was developed by researchers in Kanpur Genetic
% Algorithm Labarotary and kindly visit their website for more information
% http://www.iitk.ac.in/kangal/


%  Copyright (c) 2009, Aravind Seshadri
%  All rights reserved.
%
%  Redistribution and use in source and binary forms, with or without 
%  modification, are permitted provided that the following conditions are 
%  met:
%
%     * Redistributions of source code must retain the above copyright 
%       notice, this list of conditions and the following disclaimer.
%     * Redistributions in binary form must reproduce the above copyright 
%       notice, this list of conditions and the following disclaimer in 
%       the documentation and/or other materials provided with the distribution
%      
%  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
%  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
%  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
%  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
%  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
%  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
%  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
%  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
%  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
%  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
%  POSSIBILITY OF SUCH DAMAGE.

%% Simple error checking  错误处理
% Number of Arguments
% Check for the number of arguments. The two input arguments are necessary
% to run this function.
%确认必要的两个输入已经定义
if nargin < 2
    %error('NSGA-II: Please enter the population size and number of generations as input arguments.');
    error('NSGA-II:请输入种群大小和迭代次数！');
end
% Both the input arguments need to of integer data type
%两个输入都需要是整数
if isnumeric(pop) == 0 || isnumeric(gen) == 0
    %error('Both input arguments pop and gen should be integer datatype');
    error('NSGA-II:两个输入参数必须是整数！');
end
% Minimum population size has to be 20 individuals
%种群大小至少为