Our Program

The cloud application that we will be using will be Google’s App Engine. Joseph has outlined in a previous post the method we will be using to post our application to the web. The application we have chosen is a random number generator game that has a user select a number that is between one and a hundred. The user will continue to guess a number until the number he or she selects is the same as the one the program has generated.

Cloud Computing

“Cloud computing is Internet-based ("cloud") development and use of computer technology ("computing"). The cloud is a metaphor for the Internet, based on how it is depicted in computer network diagrams, and is an abstraction for the complex infrastructure it conceals.[1] It is a style of computing in which IT-related capabilities are provided “as a service”,[2] allowing users to access technology-enabled services from the Internet ("in the cloud")[3]without knowledge of, expertise with, or control over the technology infrastructure that supports them.[4] According to a 2008 paper published by IEEE Internet Computing "Cloud Computing is a paradigm in which information is permanently stored in servers on the Internet and cached temporarily on clients that include desktops, entertainment centers, tablet computers, notebooks, wall computers, handhelds, sensors, monitors, etc."[5]
Cloud computing is a general concept that incorporates software as a service (SaaS), Web 2.0 and other recent, well-known technology trends, in which the common theme is reliance on the Internet for satisfying the computing needs of the users. For example, Google Apps provides common business applications online that are accessed from a web browser, while the software and data are stored on the servers.”

From: http://en.wikipedia.org/wiki/Cloud_computing



Cloud computing is great for software as a service(SaaS). The following from InfoWorld shows as much.

“This type of cloud computing delivers a single application through the browser to thousands of customers using a multitenant architecture. On the customer side, it means no upfront investment in servers or software licensing; on the provider side, with just one app to maintain, costs are low compared to conventional hosting. Salesforce.com is by far the best-known example among enterprise applications, but SaaS is also common for HR apps and has even worked its way up the food chain to ERP, with players such as Workday. And who could have predicted the sudden rise of SaaS "desktop" applications, such as Google Apps and Zoho Office?”

How to upload an Application on Google's Cloud

If you have an idea on creating an application for the web, look no further. It actually take a few simple steps to get your application on the web. First, you have to have a google account in order for upload your application. If you don't have an account, you can register from the homepage of Google. The second step to getting you application on the cloud is to go to the URL . Here, you can click on the "Create an Application" button which directs you to a webpage that gives you full instructions to create the application. After finishing the instructions, you must go back to your application program and type in the following command: appcfg.py update helloworld/ . Once you type and run this command, your application is upload onto the cloud for everyone to see. The link provided ( ) is another instructional on how to create and upload your own application.

Chapter 7

Alright, to be perfectly honest, I seem to be having a lot of difficulty with some of these programs that are in the book. I think I might be using the wrong GUI. I’ll bring my computer in to our meeting tomorrow so we can sit down and look at it. I also have a couple questions about chapter 5 and 6 that are bothering me.

In chapter 7, we are introduced to modules. Modules create a named scope for functions and data, but they are simpler than classes and objects. They let you separate your program into named pieces without having to use classes. Much of Pythons flexibility comes from its ability to use modules to expand its features. For example, there could be a networking module or an operating system module, etc.

In order to use a module, you have to first install it in the system. The easiest way to do this is to use the import command:

Import sys

This line will import the module named sys which contains services Python offers that mostly involve system-specific items.


To create a module, all you have to do is create a file with what you want to call it and the extension “.py”. In the book they use “Foods.py”. When we’re finished, we can import it using the name Foods without the extension. Below is a line of code that imports the Food module:

>>>import Foods
>>>dir(Foods)
[‘Fridge’, ‘Omelet’, ‘Recipe’, ‘_builtins_’, ‘_doc_’, ‘_file_’, ‘_name_’ ]
>>>

This lets us use the Fridge, Omelet, and Recipe classes. In order to access them now, we have to use Foods.Fridge, Foods.Omelet, and Foods.Recipe.

Chapter 6

Classes and objects are a major part of computer programming. In python, they serve as the same purpose as every other language out there. If you want to clarify a class, you need to type in the keyword, class. Lets make a class called Apartment.
class Apartment:

You must add a colon at the end of the statement. A common practice with Python programmers is to capitalize the first letter of their class. When you have more than one word for a class then you capitalize the first letter of the next word.

You can create objects very easily in Python. Once you create a class you can then create an object. This is done by usually assigning a letter to a class and assigning it blank parameters.

class Apartment:
r = Apartment()
(Note that we indent. As you work through as class, you must indent for it to work. Objects or methods cannot be underneath directly under your class. )

The primary setup of creating a class with method and objects go by.

Class
Methods
.
.
.
Objects

We learned earlier how to create methods by writing def in front of the method.
In order to get a full understanding of this chapter please look at the book. You must read the example in the book because it lays everything out. The example is really good if you forget how to do things we learned in earlier chapters.

Chapter 5

At the beginning of this Chapter, we learn how to make our code into a file. I will not touch up on this because it is just like saving any other type of file. The main focus of the chapter is along the lines of try and catch. This is the reason why I had trouble because I have not dealt with this in Java yet so it was all new to me. After speaking with Dr. Piercy, I started to understand this material. If you know how to use a try and catch, then this chapter will be easy for you. For those of you who don't, try and catch is a function you can use in Java. The try portion is along the lines of a method. You want the function to "try" and execute it. The Catch portion is the area where you right an exception to the action. An example of this is trying to hook up to a database. Your code could be perfect in the "try" area but you the file you are trying to reach isn't there. The catch functions catches that the file is up and you can have it return back to you as "Cannot connect to file." This is helpful because it saves you time looking at your code trying to find out what the problem is when really, your code is fine.
With this understanding we move onto Python. If you want to write out this try catch function this is how you can go abouts.

def in_fridge ();
" " " This is the comment area where you can describe your definition" " "
try:
count = fridge(wanted_food)
except KeyError:
count = 0
return count

The problem that I was running into was when entering this data, I kept getting errors. The example above is straight out of the book. What you must do is have your try and except line up with one another while the actions inside must be indented in. This is just a structure that Python abides by. I recommend you create your own example over and over to understand the structure and the set up.
With the definition above, you see that we put a parameter which is wanted_food. Say you wanted to find how many bananas were in the fridge. All you would have to type out is:

wanted_food = "bananas"
(You are assuming that you added values to fridge earlier. For instance, fridge = {"bananas" : 3, "oranges" : 4})

Chapter 5 - Andrew

I'm with Joseph at the moment. I'm going to need a little more time reading and playing with Chapter 5 before I can post about it. I want to understand it a little better then I'll write about it.

I still need to post the schedule and about the difference between mutability and immutability. Also, I didn't know there was a meeting yesterday, I apologize for missing it.

Chapter 4 Conclusion

In the last post, I covered everything from Chapter 4 except for loops. There are two types of loops that we learn about in Chapter 4. These are “for…in” loops and “while” loops.

In a “while” loop, the operation will first check and see if it’s test condition is True. If it is, it will evaluate the indented statements. When it is done, it will go back and see if the test condition is still true. If it is, it will continue going through this process until the test condition returns False and then the program will move on.

A “for…in” loop is similar, but has fewer steps. In the first part, you give a name that you’ll use inside the indented code. In the second part, you give a sequence which takes each element and assigns the value of the element to the name you provided in the first part.

I don’t completely understand what the book is saying exactly and it just sort of throws in the pop method in the “while” loop without really saying what exactly it does.

Sometimes in writing these loops you run into an infinite loop that doesn’t stop. In order to stop this, you can use “break” at the end of the indented section.

Both “for…in” and “while” loops can have an else statement, as long as they’re not stopped by a “break”. This is used when the test condition is False and allows an alternative event to take place.

Another feature that is used a good bit with loops is “continue”. Instead of terminating the program like “break” does, “continue” just tells the loop that you want to skip the rest of the current repetition of the loop.

This concludes Chapter 4.

Chapter 5

I have run into a little problem with Chapter 5. Seeing I have been learning Java and Python at the same time, I have been fortunate enough to learn the same methods at the same time. This chapter is brand new to me and I am somewhat confused. Today's meeting will allow me to discuss the chapter more in depth to gain a better understanding and will be able to post sometime today. Sorry for this problem.

Chapter 4 Continued

Since it won’t allow me to go back and edit any of Joseph’s posts this is a continuation of Joseph’s on Chapter 4.

It is possible to have an if statement within another. For example:

sandwich_ingredients = {“ham”:3, “cheese”:2}
fridge_contents = {“ham”:10, “milk”:5, “pepper”:1, “cheese”:3}
have_ingredients = [True]
if fridge_contents[“ham”] > sandwich_ingredients[“ham”]:
have_ingredients[0] = False
have_ingredients.append(“ham”)

if fridge_contents[“cheese”] > sandwich_ingredients[“cheese”]:
if have_ingredients[0] == True:
have_ingredients[0] = False
have_ingredients.append(“cheese”)

In order for the code to continue on to the second if, also known as a nested if, the first one must be true.


That’s all I have for now. I’ll come back later and add while and for loops as well as if-else statements.

Chapter 3 Continued

Since it won't let me go into Joseph's old posts, I am creating an entirely new one with related data.

This post goes into more detail with some of the things Joe touched on in his previous post for Chapter 3. In creating variables, there are a few certain words that you can’t use because Python has them saved for special functions. These words are: and, assert, break, class, continue, def, del, elif, else, except, exec, finally, for, from, global, if, import, in, is, lambda, not, or, pass, print, raise, return, try, while, or yield. You also can not start your variable with a number or a non-alphabetical character such as a dollar sign, a pound sign, an asterisk, etc. You can, however, use the underscore character.

Other information types, aside from numbers and strings, which are built into Python are tuples, lists, and dictionaries. Tuples are sequences of values that are individually accessible. Tuples are used when you want to assign values to match more than one format specifier in a string. They are created by using normal parenthesis.

A list is similar to a tuple. Lists are created using square brackets. Other than the brackets, the main difference between a list and a tuple is that a list can be changed after it has been created. To add one item to the end of a list, you use the append method. For example if you had a list named vehicles, you would add a jet ski to the list by coding the following:
vehicle.append(“jet ski”)

If you want to add more than one item to the end of a list, you must use the extend method. For example:
Vehicle.extend(“jet ski”, “moped”, “train”)

There is another way to grow a list. That is through appending a sequence. If you had a list that you wanted to combine with another list, you can just add it at the end. Say you took your vehicle list and wanted to add a list of brand names to it. It can be done as follows:

vehicle = []
vehicle.extend(brand_name)
vehicle
[‘jet ski’, ‘moped’, ‘train’, ‘Kawasaki’, ‘Sea Doo’]

A third type of class is dictionaries. They are similar to tuples and lists. The difference between dictionaries and tuples & lists is that data is stored by names that you choose rather than their numeric order. Ex:

movie_choices = {}
movie.choices[“action”] = “Terminator 2”
movie.choices[“comedy”] = “Superbad”
movie.choices[“drama”] = “The Count of Monte Cristo”

Another way to create a dictionary while assigning keys (the words within the square brackets) and values (what comes after the equals sign) is as follows:

movie.choices = {“action” : “Terminator 2” , “comedy” : “Superbad” , “drama” : “The Count of Monte Cristo”

To find out what the keys of a dictionary are, you have to type the following:

movie_choices.keys()
[‘action’, ‘comedy’, ‘drama’]

The same thing works for finding the values:

Movie_choices.values( )
[‘Terminator 2’ , ‘Superbad’ , ‘The Count of Monte Cristo’]

Chapter 4

Comparing Values is the theme for this chapter. Comparing values is simple, all you have to do is double equal signs to see if it is the same.

1==1

True

1==2

False

You can do the same with strings not just numbers. If you want to see if they are not equal, the symbol is  != . 

1 !=0

True

When you have strings, you can access all methods that a string normally has. The example in the book is good:

gourd = "Calabash"

gourd.lower()

  "calabash"

gourd.uppper()

  "CALABASH"

Lower makes it lower case while Upper makes it all uppercase. 

The word not provides the opposite of the truth value that follows it. The not operation applies to any test that will result in a true or false outcome. 

not 9 > 2

 False

Now we are onto IF statements. This if statement will allow you to get decisions made.

if 5 > 8:

   print "No, it is not"

if 5 <>

   print "Yes, it is"

You can place the if statements within tests. 

Chapter 3 Continued..

The type of bracket you use is very important. You have seen us use () when we are inserting data. When you print off the data inside the brackets like  monkey = ("banana", "smoothie", "tastes good"), you get everything inside of that bracket. In Python, you can reference the values inside.

print "I want to access the second value which is %s" %monkey[1]

I want to access the second value which is smoothie

Remember that the counter starts at 0 , so if you wanted to get the word banana the ending would say %monkey[0] .

If you forget how many values are inside the bracket, you can type in the len to find out how many is in there. An example is print "%d" % len(monkey) which will spit out the result 3. 

You actually access a tuple through another tuple. Don't try to picture it now, it is better to look at it in layers.

monkey = ("banana", "smoothie", "tastes good")

cheetah = (monkey, "fast")

print "%s" % cheetah [0][0]

    banana

print "%s" %cheetah[0][1]

    smoothie

One specific rule involving tuples is that if you have only one element, you must follow it will a comma.    monkey = ("banana",)

Chapter 3

In Chapter 3, we will be learning to use variables. We start off with assigning values to names. Python makes it is to do so. An example of creating variables is:

first_string = "Boston"

second_string = "New York"

first_number = 2

second_number = 3

print " The first variables are %s, %s, %d, %d" % (first_string, second_string, first_number, second_number)

'The first variables are Boston, New York, 2, 3

The name in which you use doesn't relate it to the data that you are inputting. You can name it whatever way you want, but we named it in the above example in correlation what the data was. I could have named "Boston" this: first_city or first_number . This would have still given the data.

A great example of how to label for you own needs is:

lightbulbs_in_closet = 10

lightbulbs_in_lamps = 12

You can also alter the named values. It is quite simple:

lightbulbs_in_closet = 10

lightbulbs_in_closet = lightbulbs_in_closet + 4

lightbulbs_in_closet

       14

The only thing that you cannot due with naming can be found at the bottom of pg. 29. This gives you a list of words that will not work because they are built-in words that are reserved for special use to prevent any confusion.

Chapter 2

Chapter 2 involves using numbers. The great thing about Python that I have noticed is that, if you don't know what type of number it is, then it will report back to you what type it is. I tested this out by trying out some types:

type(1)

type(99999999999)

type(4.0)

I wanted to create an imaginary number and it ended up being real simple. All you do is type the equation you would see on a test:

12j +1

(1+12j)

If you want to print out the format specifiers in Python, you can put % in front of it.

print "Lets print out the format specifier %%D"

'Lets print out the format specifier %D'

A cool feature I noticed with Python is that when you do math and get an answer like 300.666666667, when you print this answer it will come out precise like 300.67.

Python is neat along the lines of, if you have a math problem to do, you can type it in exactly how it looks and it will process the answer for you. 

The exercises at the end of the book are helpful with applying all the great features of numbers in Python.

Chapter 1

Its official, we are under way with our learning of Python. Chapter 1 is to introduce you to this new language. This will be prevalent throughout the following 2 chapters. If you are a beginning programmer, like me, at the end of this chapter we will have learned some simple guiding principles for programming. A key concept that Python wants the programmer to do is to think in blocks. This blocking technique allows you to think about larger projects in little pieces. This allows the programmer to make it understandable in many parts so you can extend the program farther if need be.  So for this first chapter, I just wanted to experiment with different types of strings.  The first thing I entered in was to use quotes: 

"Let see how python works" . This came back with the response 

'Let see how python works'.  

If I want to split the sentence up all I need to use is \n.  \n stands for new line. The only way for it to read it as a special character, you must have it translated to print.  

"Let see how \n  python works" won't make a new line.

a) print "Let see how \n python works"

'Let see how 

python works'

(The exercises clarify how \n works)

If you want to combine strings, it is just like Java. All you need is a + in between what you are writing.  

 

How To Get Python

In order to start things off, we need to sit down and download the Python program. Listed below is a tutorial of where and how to achieve this program.

This tutorial is for Windows Users:

1) Open the link below in a new window to the python website.
http://www.python.org/

2) On the left hand side, you will see a tab that is called "Windows Installer"

3) Once you click that, a file download window will pop up. Click Save and save it to a location where you will be able to find it.

4) The Python download tutorial should come up. Below is a video to go abouts doing this installation process. Start the video at 1 min 2 sec.

Video Tutorial of Running Python and Quick Beginner Tutorial

For Mac Users:

If you have recently purchased a Mac in the last 2 years, you already have it. The thing is, how do you execute the program.

1) Go into the Mac's Finder and type in Terminal.

2) Click on the program Terminal and type in Python.

3) Once typing in Python, press Enter and you have just opened Python.

*Note: Look at what it says, if it says "Python 2.5.2" then you are good. Some may say "Python 2.5.1" which is fine but it is not the most up to date version.

(For those Mac users who purchased their computer longer than two years follow these instructions or have an older version.)

1) Click on the link below to get to the official Python webpage.
http://www.python.org/

2) Look on the left side of your screen and click on the "Download" tab. This will bring you to another page.

3) Again, look on the left hand side under "Download"

4) Where it says "Macintosh," click on it.

If you cannot find Macintosh, this is a link to the website : Python for Mac

5) Find out what your operating software is for your Mac to choose which install package is good for you. This website gives you the links of which to install and will makes things much easier for you.

One of my favorite web comics is XKCD and they have a few strips that talk about Python. Links are below:

Comic 1

Comic 2

Comic 3


~Andrew Hayes

August 31, 2008

Went to Barnes and Noble and Borders and both stores were out of the book we will be using this semester. Ordered them from Amazon.com when I got home. Book should arrive in about a week.

Beginning Stages of Python

Seeing that major companies have started using the computer
programming language Python, Dr. Piercy, Andrew Hayes, and
I thought that it would be appropriate to start blogging about
our experience with it. Dr. Piercy and Andrew have some
background in programming while me on the other hand is just
starting from scratch. Posts will be entered from both of us which will
allow you to get three perspectives on our journey with Python.

After careful research and reading, I have decided to learn
python from the book, "Beginning Python" by Peter Norton,
Alex Samuel, David Aietel, Eric Foster-Johnson, Leonard
Richardson, Jason Diamond, Aleatha Parker, and Michael
Roberts. At first glance, I wanted to use the book that the
website, http://www.blogger.com/www.python.org , endorsed but as I was reading through
it, I realized it was a little too technical. In the book, there were
not a lot of exercises to complete. With the book I chose, there are
activities along the way, while at the end of each chapter, there
are exercises to put your knowledge you just learned to the test. Also,
what I liked about this book is that you can obtain the chapters source
code from http://www.wrox.com/ , which is where you can also seek technical
help if your code is not working. All in all, we are excited to learn this
program because more companies are using it. The plan of attack is by
chapters.We will skip around some chapters because we don't think it is
necessary to learn.

TABLE OF CONTENTS OF BOOK

The link above is the table of contents for the book. When we post, we will indicate which
chapter we blogged about. Hope you enjoy this experience as much as we do.

SCHEDULE

Our tentative schedule is to go through two chapters a week. We will not be covering Chapter 13, 17. When we get into the advanced programming of Python, we will decide which Chapters are the most important to us based on the time left in the semester. Our goal is to allot time for us to work on a project using the Python language.