Introduction to Python and computer programming Flashcards
What is an instruction list?
A complete set of know commands (commands the computer recognises) is called an instruction list.
Different types/models of computers may have different instruction lists
What are the four elements of a language?
- Alphabet
- Lexis
- Syntax
- Semantics
What is an alphabet?
A set of symbols used to build words of a certain language
What is a lexis?
A set of words the language offers its users (a dictionary)
What is syntax?
A set of rules used to determine if a certain string of words form a valid sentence
What is semantics?
A set of rules determining if a certain phrase makes sense
The alphabet of machine learning is….
The instruction list
What is a source code?
A program written in a high-level programming language (python)
What is a source file?
The file containing the source code
How do we bridge the gap between computer and human language?
Machine language –> programming language (source code) –> natural language
What are the two methods of transforming a program from high level programming language to machine language?
Compilation and interpretation
What is compilation?
The source program (python) is translated once by getting a file containing the machine code the file can now be distributed world wide.
translated via a complier or translator
(every time the source code is modified the source program must be translated again)
What is interpretation?
The user can translate the source program each time it has to be run
The program performing transformation is called an interpreter
Source code is distributed WITH interpreter to end user
What does the interpreter do?
The interpreter reads the source code left to right, checks the lines are correct, then executes the code (or displays error)
Line by line (with some lines repeated e.g. functions)
Pros and cons of compilation?
Pros:
- execution of translated code is usually faster
- only the user needs to have the complier (end user can use code without it )
- the translated code is stored using machine learning (hard to read therefore inventions and programming tricks kept secret)
Cons:
- the compilation itself may be a very time-consuming process
- you have to have as many compliers as hardware platforms you want your code to be run on
Pros and cons of Interpretation?
Pros:
- can run code as soon as you complete it (no additional phases of translation)
- stored using programming language (python) not machine language therefore it can be run on computers using different machine languages
Cons:
- slower
- both you and the end user have to have the interpreter to run your code
Is python interpreted or complied language?
Interpreted language
if you want to program in python you’ll need the python interpreter
What are interpreted languages often called?
Scripting languages
while the source code programs encoded using them are called scripts (python script)
Who created python?
Guido van Rossum
Pros of python
Easy to learn, teach, use understand, obtain, install and deploy
Cons of python
not a speed demon
in some cases it may be resistant to some simpler testing techniques (debugging can be harder)
What are the two main kinds of python?
Python 2 and 3
They are not compatible with each other
What is CPython?
Canonical Pythons/Reference pythons developed by the PSF (Python Software Foundation)
Guido used C programming language to implement the very first version of python. all pythons from PSF are written in C language
This is the most influential Python among all the Pythons in the world.
The default implementation of the python programming language
What is Cython?
Automatically translates the Python code (clean and clear, but not too swift) into “C” code (complicated and talkative, but agile).
What is Jython?
J is for Java - python written in java instead of C
What is PyPy and RPython?
Python environment written in python like language named (RPython - restricted python)
The source code of PyPy is not run in the interpretation manner, but is instead translated into the C programming language and then executed separately.
PyPy is rather a tool for people developing Python than for the rest of the users.
What does IDLE stand for?
Integrated Development and Learning Environment
What is a debugger?
A tool that lets you launch your code step-by-step and inspect it at each moment of execution
Define a script
It’s a text file that contains instructions which make up a python program
What is machine code?
A low-level programming language consisting of binary digits/bits hat the computer reads and understands
