I took the Codecademy Python class several months ago when I surveyed various technologies. It appears I didn’t write a short note about it which is too bad because I now want to look over what I thought at the time. In my vague memory, they wrote it for the absolute beginner and spend a lot of time teaching basic computer programming concepts. (Variables, flow control, etc.)
Python is again as a topic of interest for me. It is one of the primary languages for working with ROS and also in a lot of machine learning/AI fields. (OpenAI gym is Python, Google’s TensorFlow is primarily focused Python, etc.) I think I should try to gain proficiency in the language but I didn’t want to go through a beginner-focused class again.
To review Python from a different starting point, I started going through the Python Foundation’s own tutorial for Python 3.6. I quickly determined the target audience are people already familiar with programming in another language and want to get up to speed in Python, which perfect for me! It was quite useful for me when the authors described Python features in terms of how it is similar to or different from C++ features.
On the flip side, I was reminded why I was down on Python: the incompatible break between Python 2 and Python 3. They’re both fundamentally the same language but in real world usage they are now effectively two different languages. Python libraries written for Python 2 could not run unmodified on Python 3, and vice versa. So they will have different install instructions, etc. Over eight years after the initial release of Python 3 the entire ecosystem is still undergoing the pain of this transition.
OpenAI and TensorFlow appears to support both Python 2 and 3, with separate setup and usage instructions. ROS has the official ambition to move to Python 3 but is currently still stuck on Python 2 due to the existing base of Python libraries.
Despite the temptation to stick with Python 2 for ROS, I decided to jump into the Python 3 tutorial and I’ll deal with Python 2 weirdness as they come up later.