Interested in flight, aircraft, or physics?

JSBSim is an open source flight dynamics model (FDM) that compiles and runs under many operating systems, including Microsoft Windows, Apple Macintosh, Linux, IRIX, Cygwin (Unix on Windows), etc. The FDM is essentially the physics/math model that defines the movement of an aircraft, rocket, etc., under the forces and moments applied to it using the various control mechanisms and from the forces of nature. JSBSim has no native graphics. It can be run by itself as a standalone program, taking input from a script file and various vehicle configuration files. It can also be incorporated into a larger flight simulator implementation that includes a visual system.

http://jsbsim.sourceforge.net/

Robert

Free AI Code for Chess

Here is a link to an article from CodeProject, "Test Driven Chess Artificial Intelligence" by Kristian Ekman:  https://www.codeproject.com/Articles/1168892/Test-Driven-Chess-Artificial-Intelligence

From the article:  This is a fully functional yet simple chess program that aims to help you understand how a chess engine works. There are already open source chess engines on the Internet which focus on high performance. This is a standard object oriented C# solution that is meant to be easier to comprehend. The focus has not been to make a fast and high rated chess engine. I have developed a working chess AI that plays descent good moves with code that you hopefully like to read. A few of the more specific goals have been to correctly implement Alpha Beta Pruning and Zobrist Hashing using C# 6.

If you are interested in artificial intelligence or computer chess, you might enjoy this.

Robert

Why Learn Pascal?

I purchased a copy of Genetic Algorithms in Search, Optimization & Machine Learning by David E. Goldman (1989).  The book has sample code in Pascal.  This is where Free Pascal comes in.  When I coded last in Pascal it was with Turbo Pascal and I enjoyed it much more than coding in C.  (I mentioned Free Pascal back in December 22, 2012 in this post:  Learning to Program with Pascal.)

If you go to the Free Pascal website and look at their documentation you can see there is a great deal of documentation and that Free Pascal is now an object oriented language.  You can download a  copy of the language (free under the GNU General Public License).  My complaint against the Genetic Algorithms book by Goldman is not that pascal is used, but that there is no license.  I have looked at the book and there is no license that permits you to use the code.  So if I typed up the code and posted it online at Sourceforge or Git Hub I would be violating copyright law, so I cannot share the code.  And the code is not available online.  You have to type the code yourself.  There was an operating systems textbook for an OS called Xinu that had a statement from the author that the code could be used and I saw people use this OS professionally, typing the code from the book.

Criticisms against Pascal being old are misguided.  The Scheme programming language is old, but it is a great educational language.  The book Structure and Interpretation of Computer Programs by Harold Abelson et al is a great book to study.  The Scheme programming language is also free.

So do not hesitate to get the book Genetic Algorithms by Goldman because the code is in Pascal.  Pascal is a nice language worth knowing and Free Pascal can be used to run the code in the book.

Robert Canright

Comparing Files in Notepad++

A couple of years ago I posted an article about installing a Compare plugin for Notepad++.  The links I used in the past have died, so here is new information.

On my copy of Notepad++, I did Plugins > Compare > About and got the window I show above.  So you can go to Source Forge (https://sourceforge.net/) and search on "compare notepad plugin" and you will see you can download Compare Plugin 1.5.6.2.bin.zip (https://sourceforge.net/projects/npp-compare/?source=directory).  Also there is a Notepad++ web page (https://notepad-plus-plus.org/community/topic/11116/compare-plugin) that lets you download Compare Plugin 1.5.6.7.bin.zip

This website (http://docs.notepad-plus-plus.org/index.php?title=Plugin_Development#How_to_install_a_plugin) has these instructions on how to install a Notepad++ plugin:

How to install a plugin

The plugin (in the DLL form) should be placed in the \plugins subfolder of the Notepad++ Install Folder. Configuration files should go in \Plugins\Config. Documentation files should go to \Plugins\Doc\ directory.
These are generic instructions. If the plugin comes with some different procedure, that procedure should be followed instead.
Once you installed the plugin, you can use (and you may configure) it via the menu "Plugins".

KDiff3
The KDiff3 tool is a little better.  It compares directories as well. I am working a job now where the client provided me with a computer that had Notepad++ installed, but not KDiff3 and the client would not give me admin privileges to install KDiff3.  So I am using the Compare plugin for Notepad++ and I'm glad I have it.

Here's what it looks like (below).  Single-click on the image at it will enlarge.

Free Computer Science Math Book

You can download in PDF a free copy of a book on Mathematics for Computer Science.  The book is Mathematics for Computer Science by Eric Lehman, F Thomson Leighton, and Albert R Meyer.

https://courses.csail.mit.edu/6.042/spring17/mcs.pdf

The book is almost a thousand pages long and it is not a cream-puff.   Leighton is with MIT.  It is used with this free on-line course: https://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-042j-mathematics-for-computer-science-fall-2010/index.htm

Some computer science work is very mathematical.  Look at the book Communicating Sequential Processes by C. A. R. Hoare.  It is very mathematical.  This is a book and topic that you might want to at least glance at so you can see another way to look at parallel processing.
Here is the book in PDF:  http://www.usingcsp.com/cspbook.pdf

Here is a Wikipedia article on Communicating Sequential Processes and another article on Tony Hoare.

Software is pretty cool.  Enjoy your reading!

Robert

C++ is Alive and Well

You might think that the C++ language, which has been around for many years, is an obsolete dinosaur.  If so, you would be wrong because C++ is very much alive and well.  Bjarne Stroustrup, the creator of C++, is a Managing Director in the Technology Division of Morgan Stanley.  Companies are still writing code in C++.  Here are a couple of open source C++ projects that are current.

Apache ActiveMQ C++ 3.9.3

IBM created the software called MQ (short for message queue).  Then IBM embedded MQ into their WebSphere product.  Now the open source community has created Apache ActiveMQ-CPP 3.9.3, which runs under the  Apache License v2.0 license.  Apache ActiveMQ runs on Red Hat Linux.

 Armadillo (C++ library)

Armadillo is a linear algebra software library for the C++ programming language. It aims to provide efficient and streamlined base calculations, while at the same time having a straightforward and easy-to-use interface. Its intended target users are scientists and engineers.  The Armadillo was last updated (version 7.800.0) February 17, 2017, which is just last month, so this is software that is very much in use.  Armadillo is open source software, so you can down-load it, study it, and use it.

C++ at Texas A&M

Programming: Principles and Practice Using C++ (2nd Edition) by Bjarne Stroustrup was developed at Texas A&M.

If you are interested in C++ programming, then you have an interest in a language still very much in use.

Robert

My Python Will Not Take a Command Line Argument

I had trouble getting my Python script to take a command line argument inside a subprocess.Popen call.   I do not mean that I had trouble with something like "python my_script.py arg".  No.  Here is what was failing for me:

import subprocess
proc = subprocess.Popen(‘executable_file.bin arg’)
proc.communicate()

What I got was "file not found" errors.  The Popen call could not recognize the argument as an argument.  It thought it was part of the file name.

I could run the command from a command line in a terminal.
executable_file.bin arg
worked in a command line.  Well, there is a way to make Popen work like a command line in a terminal/shell.  This is what works.

 subprocess.Popen(‘executable_file.bin arg’, shell=True)

The “shell=True” makes ‘executable_file.bin arg’work like it would in a terminal shell.

Robert