Python Notes: Introduction

1. The information presented here is intended for educational use.
2. The information presented here is provided free of charge, as-is, with no warranty of any kind.

Introduction

Hacking-Noodling

Online dictionaries provide many definitions of the phrase "chopper" but one I remember most means "motorcycle". Where did this originate? Starting in the 1950s, motorcycle mechanics would "chop off" unnecessary components (mirrors, fenders, etc.) to make "the bike" lighter for racing while also making it appear visually cleaner but not necessarily "street legal". The resulting motorcycle was called "a chopper" which today seems absurd because that phrase should have been used to describe the person doing the chopping, not the final product.

When I started working on computers in the 1970s, computer enthusiasts were already known as hackers because they "hacked off" the seemingly unnecessary parts of computer software so it would execute faster on the smaller (than mainframe) computers of the day. Everyone around me seemed to know that computer "hacking" was derived from motorcycle "chopping". This was still the case in 1984 when Steven Levy published Hackers: Heroes of the Computer Revolution.

Hacking acquired a negative connotation when popular newsrooms associated "hacking" with the activity of "breaking into a computer" (then, usually connected to the telephone network since the popular internet did not yet exist).

Although the phrase "hacking" currently appears to be going through a positive up swing (see: Hackerspace) I think the phrase "noodling" has fewer negative connotations.

Hacking (Noodling) with BASIC

Anyone who started playing with BASIC on personal computers in the 1970s and 1980s will recognize the importance of that language for noodling around. The creators of BASIC intended it to be used to teach computer programming concepts to FORTRAN students, but noodling around made BASIC ideal for teaching other concepts in science, engineering, and math. I am a huge fan of DFT/FFT books (especially these two: Understanding the FFT and Understanding FFT Applications by Anders Zonst of Citrus Press, Titusville, Florida) where numerous authors provided hundreds of demo programs written in PC-BASIC (a generic term I am using for this article). I am assuming they did this because BASIC programs are readable by non-programmers -AND- computers with BASIC were so ubiquitous that their readers could play with them. In fact, I am going to assume that anyone with the curiosity to learn DFT/FFT will already own a personal computer with at least one programming language.

BASIC on personal computers of the 1970s was usually implemented in ROM, and every implementation was different (Apple2, TRS-80, HeathKit-H9). Starting with the IBM-PC in 1981, Microsoft, began publishing 16-bit software products like GW-BASIC (1983),  QuickBASIC (1985) and QBASIC (1991) which worked well on 16-bit operating systems like MS-DOS (1981) up through Windows-3.11 (1992). These 16-bit language interpreters were also supported on 32-bit operating systems starting with Windows-95 through to Windows-7 via a process known as THUNKING.

The big problem today is that 64-bit computers run 64-bit operating systems, like Windows-10, where 32-bit programs are THUNKED but not 16-bit programs. Technical work-arounds exist including "setting up a virtual machine" on your 64-bit OS but why go to all that bother when all you want to do is noodle around? Perhaps it is time to ditch BASIC

Hacking (Noodling) with Python

Many people reading this will not know that Python was first created in 1990 to replace BASIC. Today, Python is primarily used to do server-side scripting on the internet/world-wide-web but also has many other uses. Here is a short list:

• popular in the scientific analysis of large data sets since the creation of a free third-party Python libraries known as NumPy and SciPy (these are just two of many)
• popular in many financial circles after Wall Street programmers noticed (during/after the 2008 financial melt down) that many "business case" decisions were based upon bad data associated with error-prone spreadsheet imports performed in a host of other languages (some estimates placed the losses due to bad spreadsheet data for one company alone at somewhere between $500M and $1B close to one billion dollars). This was one of the reasons for the creation of a free third-party Python library known as Pandas which can import most spreadsheets using only 5-6 lines of code
• popular on almost every computer platform (Windows, Macintosh, Linux, UNIX, or others) for any purpose including noodling around because it is available free of charge -AND- appears to be more consistently implemented than BASIC ever was

On top of all this, Python does not have these BASIC imitations:

• In BASIC, this statement PRINT 2^31 (two raised to the thirty-first power) fails with 32-bit signed integers (longword)
  • I have used more than a dozen different flavors of BASIC (on minis and micros) and none of them supported unsigned integers. This is not true of other languages like C/C++
• In BASIC, this statement PRINT 2^63 fails with 64-bit signed integers (quadword)
• Some modern BASIC implementations now support 128-bit signed integers (octaword) but most do not support exponentiation past 64-bits

Python3 has no difficulty with these statements:

• Typing PRINT(2**9999) (e.g. 2^9999) in the IDLE interpreter instantly yields 37x80+50 characters.
• Typing PRINT(2**99999) (e.g. 2^99999) in the IDLE interpreter instantly yields a yellow alert with the phrase "Squeezed Text (377 lines)" which can be optionally display or copied to another app via the clipboard.
• Typing PRINT(2**999999) (e.g. 2^999999) in the IDLE interpreter requires a few seconds to yield a yellow alert with the phrase "Squeezed Text (3763 lines)"

Imagine using numbers this size to access your data analysis arrays

Happy Hacking (er, Noodling)

(index of) Example Programs

External Links

• http://neilrieck.net/dh_demo.html :: Diffie-Hellman key exchange demo (web)  <<<--- click here to run real code
• https://www.python.org/
  • https://www.python.org/downloads/ -- get your python interpreter for any platform along with the IDLE integrated development environment 
  • https://docs.python.org/3/tutorial/
  • https://pythonclock.org/ - Python2.7 will not receive any security updates during/after 2020 so make sure you are using Python3
• OpenVMS Notes: floats (subtitled: fun with floats)
• Why Radians rather than Degrees?
  • https://qedinsight.wordpress.com/2011/03/14/why-radian-measure-makes-life-easier-in-mathematics-and-physics/
  • https://betterexplained.com/articles/intuitive-guide-to-angles-degrees-and-radians/
  • https://www.quora.com/Why-is-the-radian-measure-used-more-than-the-degree-What-is-wrong-with-degrees
• https://www.zdnet.com/article/python-is-eating-the-world-how-one-developers-side-project-became-the-hottest-programming-language-on-the-planet/
• https://www.zdnet.com/article/microsoft-we-want-you-to-learn-python-programming-language-for-free/