# The GNU General Public License, Version 2, June 1991 (GPLv2)

> Copyright (C) 1989, 1991 Free Software Foundation, Inc.
> 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, 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

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

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

# MTT

## Model Transformation Tools

### Bond-graph based modeling tools

MTT is a set of tools for modeling dynamic physical systems using the bond-graph methodology and transforming these models into representations suitable for analysis, control, and simulation.



---

## Introduction

- MTT uses and generates `.m` files for [GNU Octave](https://www.octave.org/).
- MTT is mainly built on the [GNU](https://gnu.org/) set of tools.
- MTT uses the algebraic package [REDUCE](https://reduce-algebra.sourceforge.io/).

- MTT is based on the bond graph language; general bond graph information is available from [The Bond Graph Compendium](https://www2.engr.arizona.edu/~cellier/bg.html) homepage.




---

## Availability

- [GitHub](https://github.com/reduce-algebra/mtt) _(Primary)_
- [GitLab Mirror](https://gitlab.com/reduce-algebra/mtt)

- [GitHub Issues](https://github.com/reduce-algebra/mtt/issues)

---

## Authors

- [Peter Gawthrop](http://www.gawthrop.net/) [\<peter.gawthrop@unimelb.edu.au\>](mailto:peter.gawthrop@unimelb.edu.au)

- [Geraint Paul Bevan](https://www.gcu.ac.uk/cebe/staff/geraint%20bevan/) [\<Geraint.Bevan@gcu.ac.uk\>](mailto:Geraint.Bevan@gcu.ac.uk), [\<geraint@enchant.me.uk\>](mailto:geraint@enchant.me.uk) [_(https://www.enchant.me.uk)_](https://www.enchant.me.uk/)




---

# Security Information

## Reporting a Vulnerability

Please use email to report any any security vulnerabilities:

- [Peter Gawthrop](http://www.gawthrop.net/) [\<peter.gawthrop@unimelb.edu.au\>](mailto:peter.gawthrop@unimelb.edu.au)

- [Geraint Paul Bevan](https://www.gcu.ac.uk/cebe/staff/geraint%20bevan/) [\<Geraint.Bevan@gcu.ac.uk\>](mailto:Geraint.Bevan@gcu.ac.uk), [\<geraint@enchant.me.uk\>](mailto:geraint@enchant.me.uk) [_(https://www.enchant.me.uk)_](https://www.enchant.me.uk/)



- [Jeffrey H. Johnson](https://prone.ws/) [\<trnsz@pobx.com\>](mailto:trnsz+reduce-algebra-mtt-security@pobox.com)

    <table>
      <tr>
        <td></td>
        <td class="example">
          <pre>
       mtt help representations
       mtt help components
       mtt help examples 
       mtt help crs
       mtt help representations &lt;match_string&gt;
       mtt help components &lt;match_string&gt;
       mtt help examples  &lt;match_string&gt;
       mtt help crs &lt;match_string&gt;
       mtt help &lt;component_or_example_or_CR_name&gt;
</pre

    </table>
    where n is an integer (unique within the label file). For example
    <table>
      <tr>
        <td></td>
        <td class="example">
          <pre>
%ALIAS  $a1  lin           
</pre
          >
        </td>
      </tr>
    </table>
    assigns the symbolic parameter to be lin. This parameter <code>$1</code> can
    then be used for passing a diofferent cr to the component (see section

    <!--docid::SEC96::-->
    <p>Component aliases are of the form</p>
    <table>
      <tr>
        <td></td>
        <td class="example">
          <pre>
%ALIAS Component_name   Component_location       
</pre
          >
        </td>
      </tr>
    </table>
    <p>An example appears in the following label file fragment</p>
    <table>

    <table>
      <tr>
        <td></td>
        <td class="example">
          <pre>
FOR ALL rho,g,vol,h,topt,bott,flowin,press
LET tktf2(rho,g,vol,h,topt,bott,effort,2,press,effort,1)
        = tank(rho,g,vol,h,topt,bott,press);      
</pre
          >
        </td>
      </tr>
    </table>
    Assuming that `tank' is not defined in a reduce file, MTT will leave it
    unresolved when generating m or c code.

        <td></td>
        <td class="example">
          <pre>
function p = tank (rho,g,vol,h,topt,bott,press)

  ## usage:  p = tank (vol,h,topt,bott,press)
  ##
  ## 

   val = press; zt = topt; zb = bott; 
   zval = 0.5*(abs(zb+(zt-zb)*val-h)+(zb+(zt-zb)*val-h));

   p = rho*g*zval + 0.5*(1+tanh((press-0.98)*500))*100000;

endfunction
</pre
          >

    Following the example of the previous section, the unresolved CR `tank' can
    be expressed in c++ code. For example:
    <table>
      <tr>
        <td></td>
        <td class="example">
          <pre>
inline double tank(const double rho, 
                   const double g, 
                   const double vol, 
                   const double h, 
                   const double topt, 
                   const double bott, 
                   const double press)


  /*  ## usage:  p = tank (vol,h,topt,bott,press)
    ##
    ##
  */

    <table>
      <tr>
        <td></td>
        <td class="example">
          <pre>
# Makefile for the Two link GMV example

all: msdP_tf.m TwoLinkP_obs.m TwoLinkP_sm.m twolinkp_sm.m TwoLinkGMV_numpar.m 

msdP_tf.m: msdP_abg.fig 
        mtt -q msdP tf m

TwoLinkP_obs.m: TwoLinkP_abg.fig TwoLinkP_lbl.txt
        mtt -q TwoLinkP obs m

TwoLinkP_sm.m: TwoLinkP_abg.fig TwoLinkP_lbl.txt
        mtt -q TwoLinkP sm m

B = 10

C = 1

D = 0

octave> 
</pre
          >
        </td>
      </tr>
    </table>
    generates the data structure rc corresponding the the bond graph of the
    system called `rc'. The following octave commands then generate the step

      installed, this may be done with the command
    </p>
    <table>
      <tr>
        <td></td>
        <td class="example">
          <pre>
  mtt sys sfun mexglx 
</pre
          >
        </td>
      </tr>
    </table>
    <p>
      which will generated the four .mex files and the .mdl file. In this case,