Category Archives: General

Source code downlinks fixed

Two readers alerted me to problems downloading the source code on the Downloads page on this web site, and the source code for my book on App Inventor graphics and animation.

A software update on the server appears to have changed how some default file directories were appended to filenames.

The problem appears to now be fixed. Thank you very much for letting me know of this problem.

Ed

Visit the primary web site at learn2c.org

This web site – appinventor.pevest.com – is no longer the primary web site for our App Inventor tutorials. However, this web site will remain here indefinitely as many people link to it, including search engines and my own e-books 🙂

The new, short and easy to remember URL is Learn2C.org as in “Learn 2 Code”

Unfortunately, for reasons I will not get into, it is not possible to integrate the two web sites together. So appinventor.pevest.com will remain “as is”, and Learn2C.org will become the primary focus point.

I am looking into having Learn2C automatically cross post to the appinventor.pevest.com web site but that has not yet implemented. But I’d like to do that for those that already follow the appinventor.pevest.com web site.

My apologies for not doing a lot of updates during 2018. I have already written some new code examples (Bluetooth LE anyone?) and am working on more in that area. These tutorials will appear once I have completed the entire series of example programs. There are also other items in the works that I cannot talk about yet.


Web site issues

First, the update to WordPress 5 did not go well with this web site. The web site is running WP 5 now but it has caused many problems, at least one of which I seem unable to work around or fix.

Second, I tried to reconfigure the web site for something I have been working on, but it appears what I wanted is not possible. This temporarily left the web site over night on 10 January 2019 (UTC) unable to handle incoming search links properly. I have backed out that change and search queries (via Google) should resume landing on the correct pages.

Third, around 31 December to 2 January, this web site was mostly inaccessible due to my ISP making a change to their network, which made their SQL database server inaccessible. This impacted multiple web sites, including the ISP’s own web site!

I am continuing to work on these issues with apologies for the inconvenience.

Most popular programming languages?

There are many surveys of programming language popularity. Many of the popular surveys have problems with the survey methodology such that they likely produce erroneous estimates of programming language popularity. For example, one survey looks at how many times each programming language is looked up on Internet search systems.

The chart, below, comes from GitHub and bases popularity on the number of “pull requests” that are made to the GitHub software repository. Using this method, JavaScript is the most popular programming language, followed by Python, Java, Ruby and PHP.

Python has become a standard for use by non-computer science students. Whether your college studies be in mechanical engineering or geology, there is a good chance you will learn Python for data analysis projects.

Java is now an old programming language, but still used especially for Android programming. It’s popularity for desktop applications is starting to diminish.

Ruby become popular about ten years ago. Ruby is based on a concept of “frameworks” that provide pre-made program skeletons which you adapt to make your own application. Ruby is very popular for quickly creating web-based applications.

PHP pre-dates Ruby – PHP is a script language that runs on the server side of a web application. PHP is very easy to learn and couples easily with MySQL databases, making the combination a great solution for web-based, database-backed applications.

Finally we get to the “C” derived languages including C, C++ and Microsoft’s cousin C# (a very powerful language with great development tools.). C dates back to about 1970 or so.

C++ was developed in the 1980s and added object oriented programming to C and has since expanded in many ways. C and C++ are commonly “compiled” into machine instructions for each CPU and are used for high performance applications, including operating systems, video games and media applications.

C# has features resembling Java and C++ – but in a more modern design. In some ways, C# is where some wish C++ had gone

Capture

appinventor.pevest.com has moved to learn2c.org

In the spring of 2017, this web site – appinventor.pevest.com – was moved to https://learn2c.org (or an alternate address https://appinventorplus.wordpress.com/)

The move was made for technical and practical reasons. Visit https://learn2c.org for updates made through out 2017 and into 2018.


However, things have changed since then and as of the spring of 2018, this web site may return to here. If that happens, the plan is for the new learn2c.org address to point here as well.

Why return?

Many of the technical issues that caused to migrate a year ago have gone away or been solved.

The learn2c.org web site is hosted at WordPress.com and it appears Google down ranks WordPress web sites in search results. This old appinventor.pevest.com site – even without having been updated in a year, continues to receive many times more visits as a result of searches than does the WordPress.com hosted web site!

Finally, WordPress raised their hosting price last year.