macloo / python_notes

My notes for reference - while learning Python 2.7

Python Notes (Python 2.7)

In trying to learn Python, I have used several resources. I have produced a lot of files, some of which I probably will never need again.

In this repo, I am saving my files to which I expect to return, for reference.

The tests/ directory contains trivial small files, referenced in some of my notes.

The Files

• alien_while_loop.py

  Use of random number to make a simple fight scene; if-elif-else; while-loop

• builtin_functions.py

  10 useful built-in functions, used in examples.

• classes_objects.py

  Demo of how to create classes, with their attributes and internal functions. How the functions are called. How to pass one class into another class — in this case, making all "customers" also "people."

• format_strings.py

  Demo of how using a different formatter produces different output.

• lambda_and_map.py

  How to use lambda (Python's anonymous function construct) and map(), a built-in function that's kind of like a for-loop in that it runs a function on each item in a list or a range. Handy!

• lists_practice.py

  Things we can do with lists.

• modulo_test.py

  Demo showing how modulo (modulus) works: Test a number to see if it is prime.

• options_for_function_args.py

  These options can make the arguments more flexible. One option is to set a default value. Another is to say the number of arguments might vary.

• print_python_keywords.py

  Short program that prints all Python keywords.

• read_write_easy.py

  Very basic read and write for files: open(), read(), write(), close().

• split_string_make_dict.py

  Split a string on a char (e.g. ",") to make a list. If the resulting list items are splittable pairs, you can use a for-loop to build a dictionary from the list.

• string_searches.py

  Run various tests on a string to find out whether it would be okay to use it as a filename.

• try_except.py

  Some simple examples of error handling. Students sometimes want to use an if-statement instead, but this is better because you can catch specific types of errors. Also, use of finally:

• tuples.py

  Examples of tuples. Unlike a list, a tuple is immutable.

• turtle_tests.py

  Learning to use Python's turtle module.

• useful_modules.py

  Tests with copy, random, time, pickle (for saving binary data out, as from a game, and then reading it back in).

• wrapping_02_notes.py

  Examples based on a Python intro. Using for-loops to get keys, values from a dictionary is useful. Good for a fast review of basics. Also if x in y:

• write_read_file.py

  Writing non-text data into a file as text and (awesomely) reconstituting the data back into Python objects as you read it out of the text file.

Files in /tests

Very trivial small files to show me how something is done.

Files in /texts

• firstamendment.txt - dummy text file

• p_data_types.txt

• p_escapes.txt

• p_keywords.txt

• p_operators.txt

• p_string_formatters.txt

  My notes about these, following LPTHW ex. 37.

• p_style_guide.txt

  My notes about Python style (from PEP 8).