gnulicense.m

这是一个很适合研究和学习用的电力系统仿真软件

% 		    GNU GENERAL PUBLIC LICENSE
% 		       Version 2, June 1991
%
%  Copyright (C) 1989, 1991 Free Software Foundation, Inc.
%  59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
%  Everyone is permitted to copy and distribute verbatim copies
%  of this license document, but changing it is not allowed.
%
% 			    Preamble
%
%   The licenses for most software are designed to take away your
% freedom to share and change it.  By contrast, the GNU General Public
% License is intended to guarantee your freedom to share and change free
% software--to make sure the software is free for all its users.  This
% General Public License applies to most of the Free Software
% Foundation's software and to any other program whose authors commit to
% using it.  (Some other Free Software Foundation software is covered by
% the GNU Library General Public License instead.)  You can apply it to
% your programs, too.
%
%   When we speak of free software, we are referring to freedom, not
% price.  Our General Public Licenses are designed to make sure that you
% have the freedom to distribute copies of free software (and charge for
% this service if you wish), that you receive source code or can get it
% if you want it, that you can change the software or use pieces of it
% in new free programs; and that you know you can do these things.
%
%   To protect your rights, we need to make restrictions that forbid
% anyone to deny you these rights or to ask you to surrender the rights.
% These restrictions translate to certain responsibilities for you if you
% distribute copies of the software, or if you modify it.
%
%   For example, if you distribute copies of such a program, whether
% gratis or for a fee, you must give the recipients all the rights that
% you have.  You must make sure that they, too, receive or can get the
% source code.  And you must show them these terms so they know their
% rights.
%
%   We protect your rights with two steps: (1) copyright the software, and
% (2) offer you this license which gives you legal permission to copy,
% distribute and/or modify the software.
%
%   Also, for each author's protection and ours, we want to make certain
% that everyone understands that there is no warranty for this free
% software.  If the software is modified by someone else and passed on, we
% want its recipients to know that what they have is not the original, so
% that any problems introduced by others will not reflect on the original
% authors' reputations.
%
%   Finally, any free program is threatened constantly by software
% patents.  We wish to avoid the danger that redistributors of a free
% program will individually obtain patent licenses, in effect making the
% program proprietary.  To prevent this, we have made it clear that any
% patent must be licensed for everyone's free use or not licensed at all.
%
%   The precise terms and conditions for copying, distribution and
% modification follow.
% 
% 		    GNU GENERAL PUBLIC LICENSE
%    TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
%
%   0. This License applies to any program or other work which contains
% a notice placed by the copyright holder saying it may be distributed
% under the terms of this General Public License.  The "Program", below,
% refers to any such program or work, and a "work based on the Program"
% means either the Program or any derivative work under copyright law:
% that is to say, a work containing the Program or a portion of it,
% either verbatim or with modifications and/or translated into another
% language.  (Hereinafter, translation is included without limitation in
% the term "modification".)  Each licensee is addressed as "you".
%
% Activities other than copying, distribution and modification are not
% covered by this License; they are outside its scope.  The act of
% running the Program is not restricted, and the output from the Program
% is covered only if its contents constitute a work based on the
% Program (independent of having been made by running the Program).
% Whether that is true depends on what the Program does.
%
%   1. You may copy and distribute verbatim copies of the Program's
% source code as you receive it, in any medium, provided that you
% conspicuously and appropriately publish on each copy an appropriate
% copyright notice and disclaimer of warranty; keep intact all the
% notices that refer to this License and to the absence of any warranty;
% and give any other recipients of the Program a copy of this License
% along with the Program.
%
% You may charge a fee for the physical act of transferring a copy, and
% you may at your option offer warranty protection in exchange for a fee.
%
%   2. You may modify your copy or copies of the Program or any portion
% of it, thus forming a work based on the Program, and copy and
% distribute such modifications or work under the terms of Section 1
% above, provided that you also meet all of these conditions:
%
%     a) You must cause the modified files to carry prominent notices
%     stating that you changed the files and the date of any change.
%
%     b) You must cause any work that you distribute or publish, that in
%     whole or in part contains or is derived from the Program or any
%     part thereof, to be licensed as a whole at no charge to all third
%     parties under the terms of this License.
%
%     c) If the modified program normally reads commands interactively
%     when run, you must cause it, when started running for such
%     interactive use in the most ordinary way, to print or display an
%     announcement including an appropriate copyright notice and a
%     notice that there is no warranty (or else, saying that you provide
%     a warranty) and that users may redistribute the program under
%     these conditions, and telling the user how to view a copy of this
%     License.  (Exception: if the Program itself is interactive but
%     does not normally print such an announcement, your work based on
%     the Program is not required to print an announcement.)
% 
% These requirements apply to the modified work as a whole.  If
% identifiable sections of that work are not derived from the Program,
% and can be reasonably considered independent and separate works in
% themselves, then this License, and its terms, do not apply to those
% sections when you distribute them as separate works.  But when you
% distribute the same sections as part of a whole which is a work based
% on the Program, the distribution of the whole must be on the terms of
% this License, whose permissions for other licensees extend to the
% entire whole, and thus to each and every part regardless of who wrote it.
%
% Thus, it is not the intent of this section to claim rights or contest
% your rights to work written entirely by you; rather, the intent is to
% exercise the right to control the distribution of derivative or
% collective works based on the Program.
%
% In addition, mere aggregation of another work not based on the Program
% with the Program (or with a work based on the Program) on a volume of
% a storage or distribution medium does not bring the other work under
% the scope of this License.
%
%   3. You may copy and distribute the Program (or a work based on it,
% under Section 2) in object code or executable form under the terms of
% Sections 1 and 2 above provided that you also do one of the following:
%
%     a) Accompany it with the complete corresponding machine-readable
%     source code, which must be distributed under the terms of Sections
%     1 and 2 above on a medium customarily used for software interchange; or,
%
%     b) Accompany it with a written offer, valid for at least three
%     years, to give any third party, for a charge no more than your
%     cost of physically performing source distribution, a complete
%     machine-readable copy of the corresponding source code, to be
%     distributed under the terms of Sections 1 and 2 above on a medium
%     customarily used for software interchange; or,
%
%     c) Accompany it with the information you received as to the offer
%     to distribute corresponding source code.  (This alternative is
%     allowed only for noncommercial distribution and only if you
%     received the program in object code or executable form with such
%     an offer, in accord with Subsection b above.)
%
% The source code for a work means the preferred form of the work for
% making modifications to it.  For an executable work, complete source
% code means all the source code for all modules it contains, plus any
% associated interface definition files, plus the scripts used to
% control compilation and installation of the executable.  However, as a
% special exception, the source code distributed need not include
% anything that is normally distributed (in either source or binary
% form) with the major components (compiler, kernel, and so on) of the
% operating system on which the executable runs, unless that component
% itself accompanies the executable.
%
% If distribution of executable or object code is made by offering
% access to copy from a designated place, then offering equivalent
% access to copy the source code from the same place counts as
% distribution of the source code, even though third parties are not
% compelled to copy the source along with the object code.
% 
%   4. You may not copy, modify, sublicense, or distribute the Program
% except as expressly provided under this License.  Any attempt