The source code of LESM, as well as its MATLAB App, can be executed on any operational system in which MATLAB can be installed. The LESM standalone application has installation versions for Windows and MacOS systems.

This is probably because of the screen resolution.

The minimum recommended resolution to avoid these issues is 1366x768. Preference should be given to a resolution of 1920x1080. It is also recommended to use the program with its interface maximized.

If you notice any scaling issues that might have occured to the graphical interface of LESM when using the executable standalone, you may override high DPI scaling behavior. To do this on windows systems, right-click on the executable file LESM.exe (not the shortcut), then proceed as following: Properties > Compatibility > Change high DPI settings > Override high DPI scaling behavior > System > Ok > Apply.

The Installer option is indicated for those who do not have MATLAB installed. This option installs the MATLAB runtime library and the executable standalone of LESM. The runtime library contains the necessary tools to run LESM without needing to have MATLAB installed or the license to install it. If you already use the same MATLAB version of the installer, it will not install the runtime library, only the executable standalone of LESM.

The MATLAB App option adds LESM as a new application in the MATLAB environment. The program can then be executed just by clicking on the app icon, without needing to have the source code.

This option contains all the script files of the LESM code and can be used to execute the program in any MATLAB version by running the file lesm.m. The source code of the the latest version, as well as old release versions, can also be downloaded from the Git repository.

The Sample Models option contains a library of models of different types that can be open with LESM to explore the features of the program.

The book version is an early version of LESM, developed to accompany the book "Análise Matricial de Estruturas com Orientação a Objetos" (Matrix Structural Analysis with Object Orientation Programming). This version has no graphical interface but can be used in the MATLAB environment as a non-graphical tool. It is intended for students and readers of the mentioned book who seek to understand the implementation of the Direct Stiffness Method. The complete documentation of this version is available, including the well commented source code and diagrams explaining the code architecture. The release version is the latest version of the program, with all the implementations made after the book was released, including the graphical interface and new analysis options. The source code of this version can also be obtained from the Download page.

Open-source software offers a free license to use and also allows anyone to inspect, modify, and improve its code. The source code of LESM is publicly available in a Git repository and can receive contributions from any interested developer, as well as used in classes on related topics.

MATLAB is a platform-independent computational environment optimized to perform engineering and scientific calculations. It provides a high-level programming language, which has an extensive library of predefined functions that are useful for implementing matrix structural analysis codes with simple commands A high-level programming language means that it is relatively easy to understand even for those who are not familiar with any programming language, making the source code of LESM accessible to students, engineers, architects, and researchers. Furthermore, MATLAB provides numerous graphical resources as well as friendly environments for developing graphical interfaces.

This programming paradigm is based on the idea of classes, data abstraction, encapsulation, polymorphism, and inheritance. These features are great facilitators for understanding the code structure and has proven to be very beneficial to the development and maintenance of flexible and extendable programs. One of the few barriers of exploring the OOP in an educational software is that some students may not be familiar with this programming paradigm. However, it can be easily presented to anyone since the idea of classes and objects seems natural in many cases and often appeals more to human cognition.

Since LESM is open-source and its code is publicly available in a Git repository, new implementations can be made by anyone in separate branches. The merge of new developments into the next release versions of LESM is subjected to the authors' approval.

Yes. LESM is open-source and distributed under the terms of the MIT License, which allows the program to be freely used by anyone according to the Terms of Use.

When citing LESM in your work, please refer to one of the technical journals publications listed in the Publications page.

Users are free to use the program for educational or professional activities. However, neither the authors, nor PUC-Rio, nor Tecgraf/PUC-Rio, nor any related institution are responsible for any use or misuse of the program and the results.

The aforementioned assume no liability or responsibility to any person or company for direct or indirect damages resulting from the use of any information or the use of any of the software made available here. The user is responsible for any and all conclusions made while using the program. There is no warranty and no guarantee.In case of any malfunction of the program, please contact the authors.

"Copyright (c) 2022 Luiz Fernando Martha, Rafael Rangel, Pedro Lopes, Claudio Horta

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE."

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