Python 3.3.2 (v3.3.2:d047928ae3f6, May 13 2013, 13:52:24) 
[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
Type "copyright", "credits" or "license()" for more information.
>>> 2 ** 2
4
>>> 2 ** 6
64
>>> 8/3.0
2.6666666666666665
>>> 8/4.0
2.0
>>> #order of operations - precedence
>>> # **
>>> # * /  //  %
>>> # +   -
>>> 4 + 3 * 2
10
>>> (4 + 3) * 2
14
>>> 8/3.0
2.6666666666666665
>>> 8//3.0
2.0
>>> 2 - 3
-1
>>> 2 - -4
6
# A helpful error message
>>> 4/0
Traceback (most recent call last):
  File "<pyshell#17>", line 1, in <module>
    4/0
ZeroDivisionError: division by zero
# An error message that isn't that useful
>>> 4 +
SyntaxError: invalid syntax
>>> help(abs)
Help on built-in function abs in module builtins:

abs(...)
    abs(number) -> number
    
    Return the absolute value of the argument.

>>> type(7)
<class 'int'>
>>> type(2.3)
<class 'float'>
>>> type("hello there")
<class 'str'>
>>> x = 7
>>> type(x)
<class 'int'>
>>> 8e+2 # 8.0 * 10 ** 2
800.0
>>> 8e-2 # 8.0 * 10 ** -2 = 8/100
0.08
>>> int(7.3)
7
>>> int(7.9)
7
>>> int("889")
889
# There isn't a way to map the string "hello" into
# an int, so you get an error
>>> int("hello")
Traceback (most recent call last):
  File "<pyshell#31>", line 1, in <module>
    int("hello")
ValueError: invalid literal for int() with base 10: 'hello'
>>> float("7")
7.0
>>> # Math versus python
>>> #In Math, "p = q + 10" is a statement
>>> #  that something is true
>>> # In Python, that's an assignment statement
>>> #x = x + 1 !!!! This makes no sense in Math!
>>> x = 3
>>> x
3
>>> x == 3
True
>>> x == 4
False
yes
>>> i = 3
>>> j = 4
>>> # in math these mean the same thing
>>> #i = j
>>> #j = i
# But they do not mean the same thing in Python
>>> i = 3
>>> j = 4
>>> i = j
>>> j = i
>>> i
4
>>> j
4
>>> i = 3
>>> j = 4
>>> j = i
>>> i = j
>>> i
3
>>> j
3
>>> 6 = j
SyntaxError: can't assign to literal
>>> "hello" = 4
SyntaxError: can't assign to literal
>>> #variables must start with a letter or
>>> # underscore
# Case matters; x and X are different variables    
>>> x = 4
>>> X = 3
>>> x
4
>>> X
3
>>> #variable names can include letters, digits and underscore
>>> percentage_amount = 3
>>> #  We ran program input.py
    #  It gets input from the shell.  You can see the run here.
    #   I typed Jan, 1000, and 50 into the python shell
enter your name: Jan
The type of name is <class 'str'>
enter the amount of money you have in the bank: 1000
The type of inBank is <class 'str'>
enter the amount of money you have in stocks: 50
You have 1050 money
>>> inBank = "1000"
>>> inStocks = "150"
# + concatenates (puts together) when it is called
# with strings
>>> inBank + inStocks
'1000150'
>>> "hello " + "world"
'hello world'
# + does sum when called with ints
>>> int(inBank) + int(inStocks)
1150
>>> #Let's look at formatting print statements
>>> total = 4700.0
>>> due = total/12
>>> due
391.6666666666667
>>> format(due)
'391.6666666666667'
>>> format(due,".2f")
'391.67'
>>> format(due,".4f")
'391.6667'
>>> print("The monthly payment is",format(due,".2f"))
The monthly payment is 391.67
>>> print("The monthly payment is",due)
The monthly payment is 391.6666666666667
>>> print("The monthly payment is",format(due,".2f"),sep="")
The monthly payment is391.67
>>> print("The monthly payment is",format(due,".2f"),sep="&&&")
The monthly payment is&&&391.67
>>> print(1,2,3,sep="*&%")
1*&%2*&%3
>>> total = 1234789
>>> due = total / 12
>>> due
102899.08333333333
>>> print("The monthly payment is",format(due,",.2f"))
The monthly payment is 102,899.08
>>> print("The monthly payment is $",format(due,",.2f"))
The monthly payment is $ 102,899.08
>>> print("The monthly payment is $",format(due,",.2f"),sep="")
# Finally, we get what we want!  
The monthly payment is $102,899.08
>>> # At the end of the class, we ran the program "columns.py"
# You should run the program, and make sure you understand 
# the output