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EECS 110: Lec 2: What is Programming?
Aleksandar Kuzmanovic
Northwestern University
http://networks.cs.northwestern.edu/EECS110-s15/
Grading
2
Note!
Grades
Exams
Based on points percentage
if perc >= .90: grade = 'A'elif perc >= .80: grade = ‘B'elif perc >= .70: grade = 'C'
Midterm Wed April 29
~ 75% Assignments
Extra ~ 5% Participation~ 25% Exams
Final Wed June 3
To pass EECS 110, you must have a passing grade on both the exams and HW. I will also give quizzes in the
class, but they will not be graded.
Getting help! • Labs
• You should attend the labs because they will have you solve about 50% of your homework
• Recitations
• There will be a recitation class each Friday (10-10:50 am): help with the rest 50% of the homework
• Office Hours
• TA1: Friday 1-3 pm (Wilkinson).
• TA2: Sunday (3-5 pm) (Wilkinson)
• Professor: Tuesday: 9-12 (Wilkinson).
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Communication • Professor:
• TAs:
• Ning Xia [email protected]
• Xitao Wen [email protected]
• Bhavita Jaiswal [email protected]
• Juan Li [email protected]
• Group e-mail:
• [email protected] (all students, TAs, and the professor)
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Teaching Assistants
Ning Xia
Xitao Wen
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Teaching Assistants
Bhavita Jaiswal Juan Li
Homework
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Assignments~ 4-5 problems/week ~ 100 points 20-25% extra credit
availableDue Sunday evening - by 11:59 pm. You can submit 3 homeworks 1 day later
Collaboration
Some problems are specified “individual-only.”
Others offer the option of working in a pair.
•You must share the work equally - typing and coaching
•Each of you should make ONE submission (2 per team)
•Be sure to indicate who your partner was at the submission site!
Honor Code
"Late Days"
Honor Code
• You may not share written, electronic or verbal solutions with other students (present or past):
• You are encouraged to discuss problems with other students, TAs, or instructors.
• You may not share written, electronic or verbal solutions with other students (present or past):
• Copying of files except those provided by the course material.
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You will have the option of working in pairs for MANY of each week’s problems: the same guidelines apply for each pair.
Book
CS for Scientists and Engineers, by C. Alvarado, Z. Dodds, G. Kuenning, and R. Libeskind-Hadas (Note: this is a preliminary draft!)
Available at: http://networks.cs.northwestern.edu/EECS110-s15/cs5book.pdf
• (there is a direct link from the documentation page)
The book is recommended, but NOT required
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Software and Web site
Web page:http://networks.cs.northwestern.edu/EECS110-s15/
Programs: Python and Idle
open source, free from
www.python.org
installation instructions on the Web site
MAKE SURE TO DOWNLOAD python-3.2.2
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Submission site
11
http://ivy.cs.northwestern.edu/users/sign_in
Username: …………… Password: …………… Submit
Submission site
12
Username: …………… Password: ……………
Welcome aleksandar
Upload your assignment
Choose a file to upload: ……………
Password ChangeOld Password: ……………
New Password: ……………
Confirm Password: ……………
http://ivy.cs.northwestern.edu/users/sign_in
Submit
Upload File
Browse...
Change Password
Logout
Submission site
13
Username: …………… Password: ……………
Welcome aleksandar
Upload your assignment
Choose a file to upload: ……………
Password ChangeOld Password: ……………
New Password: ……………
Confirm Password: ……………
How to get login/password:[email protected]
http://ivy.cs.northwestern.edu/users/sign_in
Submit
Upload File
Browse...
Change Password
Logout
Homework problems 3 and 4
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Picobot
area not covered
(yet!)
Picobotwalls
area already covered
Goal: whole-environment coverage with only local sensing…
inspiration?
Picobot
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area not covered
(yet!)
Goal: whole-environment coverage with only local sensing…
area already covered
Picobotwalls
iRobot's Roomba vacuum
inspiration!
Surroundings
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N
W E
S
Picobot can only sense things directly to the N, E, W, and S
For example, here its surroundings are
NxWxN E W S
Surroundings are always in NEWS order.
How many distinct surroundings are there?
N
EW
S
xxxx Nxxx xExx xxWx xxxS NExx NxWx NxxS
xEWx xExS xxWS NEWx NExS NxWS xEWS NEWS(won’t happen)
== 16 possible …24
Surroundings
State
Picobot's memory is a single number, called its state.
State is the internal context of computation.
State and surroundings represent everything the robot knows about the world
Picobot always starts in state 0.
I am in state 0. My surroundings
are xxWS.
Rules
Picobot moves according to a set of rules:
state
I am in state 0. My surroundings
are xxWS.
surroundings
0 xxWS 0N
direction new state
If I'm in state 0 seeing xxWS,
Then I move North, and change to state 0.
Aha!I should move N.
I should enter state 0.
Wildcards
Asterisks * are wild cards. They match walls or empty space:
0 x*** 0N
state surroundings direction new state
here, EWS may be wall or empty space
I am in state 0. My surroundings
are xxWS.Aha! This matches x***
What will this set of rules do to Picobot?
0 x*** 0N
0 N*** 1X
1 ***x 1S
1 ***S 0X
state surroundings direction new state
Picobot checks its rules from the top each time.
Only one rule is allowed per state and surroundings.
When it finds a matching rule, that rule runs.
->
->
->
->
To do Write rules that will always cover these two rooms.(separate sets of rules are encouraged…)
but your rules should work regardless of Picobot's starting location
hw0, Problem #3 hw0, Problem #4 (Extra)
Alter these "up & down" rules so that Picobot will traverse the empty room…
the empty room
Ideas for the maze?
the maze
Python and Idle
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Editor window: code Shell window: running code
Here, you can try things out at the command prompt >>>
Here, you can save and change programs. Hitting F5 runs your
program over in the shell
If statements (1)
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name = input('Hi... what is your name? ')
if name == ’Ning': # is it Ning? print('x1’) else: # in all other cases... print('x2’)
print('x3’)
hw0pr1.py Homework 0, problem 1
If statements (2)
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name = input('Hi... what is your name? ')
if name == ’Ning‘: print('x1’) else: print('x2’)
print('x3’)
CS != programming
What is computer science (CS)?Take EECS 101
CS != programming
What is computer science (CS)?Take EECS 101
"not equal to"
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Programming
CS
a vehicle, not a destination
programming : CS ::
machining : engineering
grammar : literature
equations : mathematics
CS != programming
CS == computing science
Study of complexity (or complex things?)
How can it be done?
How well can it be done?
Can it be done at all?
CS == computing science
Study of complexity (or complex things?)
How can it be done?
How well can it be done?
Can it be done at all?"equal to"
Information
What information does Google work with?What technical problems does Google face?
Information
What information does Facebook work with?What technical problems does Facebook face?
Information
What information does the iPhone work with?What technical problems does the iPhone face?
Computer Science and Information
Information is life’s fundamental building block
CS is a set of fundamental techniques for understanding and leveraging this information
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What is programming?
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Programming as learning a foreign language
1) Expect it to be different!
2) Don’t feel you need to memorize it
3) Immersion == Experimentation
The foreign language of Python…
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syntax?How it looks
semantics?What it does
intent?What it should do
name = input('Hi... what is your name? ') print # prints a blank line
if name == ’Ning': # is it Ning? print( name, '??’) print(‘You must be a TA!')
elif name == ‘Aleksandar’: # is it Aleksandar? print( ‘You must be an instructor!')
else: # in all other cases... print( 'Welcome to Python,', name, '!')
The foreign language of Python…
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syntax?How it looks
semantics?What it does
intent?What it should do
name = input('Hi... what is your name? ') print # prints a blank line
if name == ’Ning': # is it Ning? print( name, '??’) print(‘You must be a TA!')
elif name == ‘Aleksandar’: # is it Aleksandar? print( ‘You must be an instructor!')
else: # in all other cases... print( 'Welcome to Python,', name, '!')
The foreign language of Python
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syntax?How it looks
semantics?What it does
intent?What it should do
• how punctuation is used• the language keywords that are used• use of whitespace• peculiarities of formatting• how behavior is affected …
HW 0, Problem 2
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syntax?How it looks
semantics?What it does
intent?What it should do
• Save hw0pr1.py under a new name, hw0pr2.py
• Change hw0pr2.py to play rock-paper-scissors.
It does not have to play fair!
Feel free to add to the dialog, if you wish…
• Submit your hw0pr2.py in the usual way.
Stepping back from Python for a moment…
