Week 10
Monday
More about Pointers
pointer - variables that hold address of other variables
declaring a pointer with *
de-referencing a pointer with *
find the address of a variable with &
Dynamic memory allocation with new, give it back with delete
Memory leak
 
Tuesday
Subtopic
Wednesday
Thursday
Friday
Python Introduction
 
  • Install from https://www.python.org/downloads/
  • Idle - IDE that comes with python but something like notepadd++ or pyCharm is better
  • Python Shell - c:\python34\python.exe
  • Python Language
  • Interpreted language - Not compiled, slower
  • Dynamically type - no strict variable types, no need to declare variables just start using them
  • A white-space language - delaminated by spaces
  • Running from the command prompt
    • python programName.py
    • run the python program passing is the name of your .py file as the only command line argument
  • variables
    • no declaration
    • name must start with a letter
    • name may contain a letter, number, or underscore
    • 5 general variable types in python
      • Numbers
      • Strings
      • Lists
      • Tuples
      • Dictionaries
  • Arithmetic operators  
    • like c++ -     +, -, * ,/ %
    • exponential -  **
    • floor division //
    • order of operations is applied as expected
  • Simple examples
  • output  - print("Hello World")
  • output without new line - print("Hello World", end = "")
  • input - myName = input("Prompt text?")
  • myName is a variable that holds some type of input
  • input number example
  • comment - line begins with #
  • No difference between single and double quoted strings.   'apple' is the same as "apple"
  • Conditional statements:
    • Everything inside the conditions should be tabbed over one tab space.
  • if elif else
  • Short circuit boolean expressions are applied
  • boolean operators "and" and "or"
  • Loops
    • Everything inside the loop should be tabbed over one tab space.
  • while
  • for
  • Functions
    • def functionName(parametesr):
    • Everything inside the function should be tabbed over one tab space.  
  • "void " function example
  • function that returns a value
  • function parameter example
  • scope of variables made inside a function... it is only in the function
  • optional parameter
    • def fun(n = None):
    • test for none like this:  if n is None:
  • import
  • mulit line string - ''' test that has multiple lines ''''
    • Just place three single quotes on each end of the text
  • lists
  • with indexes Can contain anything in one list
  • names  = ['Emma','Eli','Eden']
  • there can be lists inside of lists (picture as boxes inside of boxes)
  • names.append ('Ezra') adds a new item to the end of the list
  • names.insert('Other',1)
  • names.remove('Other')
  • len(names) - finds the number of items in the list
  • min(names) - finds the number of items in the list
  • max(names) -
  • names.reverse()
  • names.sort()
  • del names[1]
  • for loop with list
  • tuples
  • useful when you have collections of things that are not likely to be changed
  • function parameter example
  • dictionaries - example
  • random
  • strings
    • substring first n characters  - s[startIndex:length]
    • substring last n characters  - s[-n:]
    • substring all but last n characters  - s[:-n]
    • find index of string in string (case sensitive) - string.find("query")
    • s.isalpha() - is alpha
    • s.isalnum() - is all number
    • len(s) - length of the string
    • s.replace("text", "other text")
    • s.strip() - removes all white space
    • s.split(",") - makes a list of strings by parsing the original string where the commas where
  • File IO
    • file_handle = open("filename.txt","wb")
    • file_handle.write(bytes("Text to write to file", "UTF-8"))
    • file_handle.close()
    • file_handle = open("filename.txt", "r+")
    • text = file_handle.read()
    • os.remove("filename.txt") - deletes the file
  • OOP
    • class key word
    • __ - two underscores proceed private data member names
    • encapsulation
    • dog class, dog test
 
  • Resources
 
 
 
 
 
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