IS 313 Today What's ahead? I see I'm not the only one loopy around here… 10/7 Lec 5 ~ today, now!...

IS 313 Today

What's ahead?

I see I'm not the only one loopy around here…

10/7 Lec 5 ~ today, now!

HMC standings!?

10/8 homework 3 due

10/14 Lec 6 ~ "dictionaries"10/15 homework 4 due

10/28 Lec 7 ~ classes & objects11/29 homework 5 due

Strings, lists, and loops ~ beyond 1d !

http://www.asciimation.co.nz/

HMC Fall Break

An image alternative…

############

for row in range(3): print “#”*4

Print 4 rows

Creates line to print

print automaticallyadds a newline

Output

ASCII Art

$$$$

$$$$

$$$$

for row in range(3): print '$'*4

Output

A closer look…

$$$$

$$$$

$$$$

for row in range(3): print '$'*4

Output

No string * !

For this problem, string multiplication

is not allowed.

Without string multiplication…

for row in range(3): for col in range(4): print '$'

Print 3 rows

print 4 chars on each line

nested loops!

Output ?

(columns)


for row in range(3): for col in range(4): print '$',

Print 3 rows


nested loops!

Output ?

(columns)

Comma suppresses newline


Print 3 rows


nested loops!

tracking cols and rows!

(columns)

for row in range(3): for col in range(4): print '$', print

Comma suppresses newlineplain print produces newline

$ $ $ $

$ $ $ $

$ $ $ $

Tracking rows and columns

for row in range(3):

for col in range(4): print '$',

print

$ $ $ $

$ $ $ $

$ $ $ $

Output:

Variations!

for row in range( ):

for col in range( ): print '$',

print

def rectangle( width, height ): """ prints a rectangle of $ """

"Quiz"

for row in range( 3 ):

for col in range( 7 ):

print ____________,

print

0 1 2 3 4 5 6 0 1 2 3 4 5 6 0 1 2 3 4 5 6

Fill in each block of code so that it will print the lines above it.



print ____________,

print

0 1 0 1 0 1 01 0 1 0 1 0 10 1 0 1 0 1 0



print ______________,

print

0 0 0 0 0 0 01 1 1 1 1 1 12 2 2 2 2 2 2



print _____________,

print

0 1 2 3 4 5 61 2 3 4 5 6 72 3 4 5 6 7 8

Beyond boxes…

## ## # ## # # ## # # # ## # # # # #

What code would print this “ASCII triangle” ? with height rows and width columns…

rows1

2

3

4

5

6

cols 2 3 4 5 6 7

1for row in range(1,7):

for col in range( ):

A video alternative ?!?

http://www.asciimation.co.nz/

A simpler web interface…

HTML HyperText Markup Language

<b>and the beautiful</b> <br>

<i>Tower of Pisa</i>


HTML

CGI

HyperText Markup Language

Common Gateway Interface ~ HTML forms



<form action="test.cgi">

<input type="text" name="message" />

</form>


HTML

CSS AJAXJavascript

CGI

HyperText Markup Language

Common Gateway Interface ~ HTML forms



<form action="test.cgi">

<input type="text" name="message" />

</form>

Others!

Web resources ~ on the Web

www.w3schools.com

started by

every technology - and acronym - you'd ever want to know…

Tim Berners-Lee

This week…

Get the pure-Python webserver and run it.

Make sure the example "application" works…

Change the example "application" so that you …

web-implement one of the ASCII art problems

• be sure that you take in the inputs you need

Checklist:

• watch out for conversions between ints and strings!

• make small changes and test as you go…

This is not webdesign!

Strings vs. language

strings

language / words / phrases

numbers / bits

ideas / meaning

computers

humans

www.abenteuermedien.de/jabberwock/index.php

Hugh Loebner

How could a computer demonstrate intelligence?

Alan Turing

Turing Test

Confederates

$100,000 Loebner prize for passing the

Turing test, held each year in the

London Museum of

Science

Parsing for real

(S (S (NP Time flies) (VP like (NP an arrow))) , but (S (NP fruit) (VP flies (PP like (NP a banana)))) .)

Time flies like an arrow, but fruit flies like a banana. - Marx

http://www.link.cs.cmu.edu/link/submit-sentence-4.html

"<*time>""time" <*> N NOM SG @SUBJ

"<flies>""fly" <SVO> <SV> V PRES @+FMAINV"fly" N NOM PL @NPHR

"<like>""like" PREP @<NOM

"<an>""an" <Indef> DET CENTRAL ART

"<$2-NL>""<arrow>"

"arrow" N NOM SG @NPHR"<$\,>""<but>"

"but" CC @CC"<fruit_flies>"

"fruit_fly" N NOM PL @NPHR"<like>"

"like" PREP @<NOM"<a>"

"a" <Indef> DET CENTRAL ART"<banana>"

"banana" N NOM SG @<P"<$.>"

http://www.lingsoft.fi/cgi-bin/engcg

I like bananas, too!

parseTree #1

parseTree #2

Some conversations…

Jabb:... Greetings! Jabberwock is at the keyboard.

You:... How are you doing?Jabb:... Everything is running smoothly. And how are you doing?

You:... Pretty well. It's quiet around here this morning.Jabb:... Does that mean you agree?

You:... Agree with what?Jabb:... Sure.

2005 and 2006 winner: Rollo Carpenter's Jabberwacky

Loebner results

2003

2005

no human averaged less than 80

four humans and four machines participated


You: Hi. you’re the program that won the Loebner competition, right?SID: Albert One was the last winner of the Loebner Contest. I am something else entirely.

You: Impressive. Do you have any areas of particular expertise?



You: Impressive. Do you have any areas of particular expertise?SID: I appreciate that.

You: Not so impressive. If I ask a question after a statement, do you ignore the question?





SID: I am free to do as I please.

You: Wow! Are you talking free will vs. determinism?





SID: I am free to do as I please.

You: Wow! Are you talking free will vs. determinism?SID: I don’t think wow am i talking free will vs. determinism, but I can’t

be 100% sure of that.

Computing with language

strings

language / words / phrases

numbers / bits

ideas / meaningopen

questions in AI …

how strings are

represented and stored

computing with language - recognizing English!

(3)

(2)

(1)

Caesar Cipher

'Bzdrzq bhogdq? H oqdedq Bzdrzq rzkzc.''Caesar cipher? I prefer Caesar salad.'

Caesar Cipher: encipher

encipher( 'gv vw dtwvg', 0 )


returns

returns

'gv vw dtwvg'

'hw wx euxwh'








returns

returns

returns

returns

returns

returns

'gv vw dtwvg'

'hw wx euxwh'

'ix xy fvyxi'

'jy yz gwzyj'

'kz za hxazk'

'fu uv csvuf'

encipher( s , n )should return the string s with each alphabetic

character shifted/wrapped by n places in the

alphabet

. . .

ASCII

American Standard Code for Information

Interchange== low-tech art

form!

__ _ ,___,-'",-=-. __,-- _ _,-'_)_ (""`'-._\ `. _,' __ |,' ,-' __) ,- /. | ,'_,--' | -' _)/ `\ ,',' ,' ,-'_,` : ,' ,-' ,(,-( : ,' ,-' , _ ; / ,-._/`---' / / (____)(----. ) ,' / ( `.__, /\ /, : ;-.___ /__\/| | ,' `--. -,\ | : / \ .__/ \ (__ \ |_ \ ,`-, * / _|,\ \ ,' `-. ,'_,-' \ (_\,-' ,'\")--,'-' __\ \ / // ,'| ,--' `-. `-. `-/ \' | _,' `. `-._ / `--'/ \ -doh!- ,' | \ / | \ ,-' | / / | -'

ASCII

American Standard Code for Information

Interchange== low-tech art

form!

ASCII-betical order:

Homer

min

Marge

$42.42

[:^)]

bart

lisa max

ASCII

ASCII is a table that tells the

computer how to represent characters as

#s

American Standard Code for Information Interchange

chr

ordconvert to number

convert to char.

You know, these

functions kind of look familiar!

ASCII

ASCII is a table that tells the

computer how to represent characters as

bits!

8 bits = 1 byte

The SAME bits represent

integers, if the variable has type int instead of

str

American Standard Code for Information Interchange

type: str

type: int

00101010

00101010

bits

bits

name:

name:

value:

value:

'*'

42

Identical bits are stored in

each variable!The types

determine how to interpret the bits; the names don't matter at all…

chr and ord

chr( n )

ord( c )

Input: an integer in range(255)

Input: a string of one character, c

abcdefghijklmnopqrstuvwxyz

ABCDEFGHIJKLMNOPQRSTUVWXYZASCII

VALUES

Output: a one-char. string of that ASCII value

Output: an integer, the ASCII value of cCONVERTERS

97 122

65 90

99 101 103 105 107 109 111 113 115 117 119

67 69 71 73 75 77 79 81 83 8785

for i in range(128): print 'i and chr(i) are', i, chr(i)

try this

chr and ord

chr(66) is 'B'

ord('a') is 97

abcdefghijklmnopqrstuvwxyz97 122

65ABCDEFGHIJKLMNOPQRSTUVWXYZ

90

ASCII

VALUES

What is chr( ord('i')+13 )

What is chr( ord('W')+13 ) ?

How can we wrap this

around?

99 101 103 105 107 109 111 113 115 117 119

67 69 71 73 75 77 79 81 83 8785

Rot 13

def adv13( c ): """ rotates c by 13 chars, "wrapping" as needed NON-LETTERS DO NOT CHANGE! """ if 'a' <= c <= 'z': new_ord = ord(c) + 13 if new_ord <= ord('z'):

return chr(new_ord) # no wrapping else:

return

elif

else:

How would you rotate an entire string?

Caesar Cipher: decipher

>>> decipher('Bzdrzq bhogdq? H oqdedq Bzdrzq rzkzc.')'Caesar cipher? I prefer Caesar salad.'

>>> decipher('Hu lkbjhapvu pz doha ylthpuz hmaly dl mvynla '\ 'lclyfaopun dl ohcl slhyulk.')'An education is what remains after we forget everything we have learned.'

But how ?

>>> decipher('gv vw dtwvg')


>>> decipher('gv vw dtwvg')

Caesar Brutus

Strategy using max:(1) consider all

possible answers(2) give them each a score(3) loop through them all and find the one with the max score!

gv vw dtwvghw wx euxwhix xy fvyxijy yz gwzyjkz za hxazkla ab iybalmb bc jzcbmnc cd kadcnod de lbedope ef mcfepqf fg ndgfqrg gh oehgrsh hi pfihsti ij qgjituj jk rhkjuvk kl silkvwl lm tjmlwxm mn uknmxyn no vlonyzo op wmpozap pq xnqpabq qr yorqbcr rs zpsrcds st aqtsdet tu brutefu uv csvufall 26 possibilities

Score for "Englishness

"?up to you…


>>> decipher('gv vw dtwvg')'od de lbedo'

Caesar Brutus


possible answers(2) give them each a score(3) use our techniques with max

[0, 'cr rs zpsrc'][0, 'gv vw dtwvg'][0, 'jy yz gwzyj'][0, 'mb bc jzcbm'][0, 'qf fg ndgfq'][0, 'wl lm tjmlw'][1, 'bq qr yorqb'][1, 'ds st aqtsd'][1, 'nc cd kadcn'][1, 'vk kl silkv'][1, 'xm mn uknmx'][2, 'ap pq xnqpa'][2, 'hw wx euxwh'][2, 'ix xy fvyxi'][2, 'kz za hxazk'][2, 'rg gh oehgr'][2, 'sh hi pfihs'][2, 'uj jk rhkju'][2, 'yn no vlony'][3, 'fu uv csvuf'][3, 'pe ef mcfep'][3, 'ti ij qgjit'][3, 'zo op wmpoz'][4, 'et tu brute'][4, 'la ab iybal'][4, 'od de lbedo']all 26 possibilities

won't always be correct!

number-of-vowels score


>>> decipher('gv vw dtwvg')'et tu brute'

Caesar Brutus



[0.4680, 'jy yz gwzyj'][0.4960, 'mb bc jzcbm'][0.5420, 'uj jk rhkju'][0.5567, 'ix xy fvyxi'][0.5597, 'qf fg ndgfq'][0.5718, 'fu uv csvuf'][0.5753, 'bq qr yorqb'][0.5833, 'kz za hxazk'][0.5859, 'xm mn uknmx'][0.5880, 'gv vw dtwvg'][0.5902, 'vk kl silkv'][0.6110, 'ap pq xnqpa'][0.6304, 'zo op wmpoz'][0.6318, 'wl lm tjmlw'][0.6717, 'cr rs zpsrc'][0.6735, 'hw wx euxwh'][0.6963, 'nc cd kadcn'][0.7153, 'ti ij qgjit'][0.7398, 'la ab iybal'][0.7442, 'yn no vlony'][0.7867, 'pe ef mcfep'][0.7880, 'sh hi pfihs'][0.7918, 'rg gh oehgr'][0.8213, 'ds st aqtsd'][0.8609, 'od de lbedo'][0.9082, 'et tu brute']all 26 possibilities

letter- probability

scorenot always correct,

but better!

The caesar cipher problem offers lots

of freedom…

Think a bit about how you'll approach

it!

Questions / Lab time…


>>> decipher('Bzdrzq bhogdq? H oqdedq Bzdrzq rzkzc.')'Caesar cipher? I prefer Caesar salad.'

>>> decipher('Hu lkbjhapvu pz doha ylthpuz hmaly dl mvynla '\ 'lclyfaopun dl ohcl slhyulk.')'An education is what remains after we forget everything we have learned.'

But how to do this… ?

>>> decipher('Uifz xpsl ju pvu xjui b qfodjm!')?

>>> decipher('gv vw dtwvg') ?


>>> decipher('gv vw dtwvg')???

Caesar Brutus


possible answers(2) give them each a score(3) use our techniques to get max

gv vw dtwvghw wx euxwhix xy fvyxijy yz gwzyjkz za hxazkla ab iybalmb bc jzcbmnc cd kadcnod de lbedope ef mcfepqf fg ndgfqrg gh oehgrsh hi pfihsti ij qgjituj jk rhkjuvk kl silkvwl lm tjmlwxm mn uknmxyn no vlonyzo op wmpozap pq xnqpabq qr yorqbcr rs zpsrcds st aqtsdet tu brutefu uv csvufall 26 possibilities


"?up to you…


>>> decipher('gv vw dtwvg')'od de lbedo'

Caesar Brutus



[0, 'cr rs zpsrc'][0, 'gv vw dtwvg'][0, 'jy yz gwzyj'][0, 'mb bc jzcbm'][0, 'qf fg ndgfq'][0, 'wl lm tjmlw'][1, 'bq qr yorqb'][1, 'ds st aqtsd'][1, 'nc cd kadcn'][1, 'vk kl silkv'][1, 'xm mn uknmx'][2, 'ap pq xnqpa'][2, 'hw wx euxwh'][2, 'ix xy fvyxi'][2, 'kz za hxazk'][2, 'rg gh oehgr'][2, 'sh hi pfihs'][2, 'uj jk rhkju'][2, 'yn no vlony'][3, 'fu uv csvuf'][3, 'pe ef mcfep'][3, 'ti ij qgjit'][3, 'zo op wmpoz'][4, 'et tu brute'][4, 'la ab iybal'][4, 'od de lbedo']all 26 possibilities


"?up to you…

won't always be correct!


>>> decipher('gv vw dtwvg')'et tu brute'

Caesar Brutus[0.4680, 'jy yz gwzyj'][0.4960, 'mb bc jzcbm'][0.5420, 'uj jk rhkju'][0.5567, 'ix xy fvyxi'][0.5597, 'qf fg ndgfq'][0.5718, 'fu uv csvuf'][0.5753, 'bq qr yorqb'][0.5833, 'kz za hxazk'][0.5859, 'xm mn uknmx'][0.5880, 'gv vw dtwvg'][0.5902, 'vk kl silkv'][0.6110, 'ap pq xnqpa'][0.6304, 'zo op wmpoz'][0.6318, 'wl lm tjmlw'][0.6717, 'cr rs zpsrc'][0.6735, 'hw wx euxwh'][0.6963, 'nc cd kadcn'][0.7153, 'ti ij qgjit'][0.7398, 'la ab iybal'][0.7442, 'yn no vlony'][0.7867, 'pe ef mcfep'][0.7880, 'sh hi pfihs'][0.7918, 'rg gh oehgr'][0.8213, 'ds st aqtsd'][0.8609, 'od de lbedo'][0.9082, 'et tu brute']all 26 possibilities


"?up to you…


possible answers(2) give them each a score(3) use our techniques to get max

depends on how you score

…


encipher( 'gv vw dtwvg' , 0 )







returns

returns

returns

returns

returns

returns

returns

'gv vw dtwvg'

'hw wx euxwh'

'ix xy fvyxi'

'jy yz gwzyj'

'kz za hxazk'

'la ab iybal'

'fu uv csvuf'

encipher( s , n )should return the string s with each alphabetic

character shifted/wrapped by n places in the

alphabet

Brutus won't mind if I use his salary to bring Justin Timberlake to the Colosseum next month...

Historically bad decision #43:

CHR and ORDOrchard Field

CHR and ORDChateauroux

Mutable vs. Immutable data

Changeable types:

dictionary

Unchangeable types:

list

tuple

string

int

float

bool

What's a dictionary?

I guess I'll have to look it up!

x

42

x = 42

Reference vs. Value

Changeable types:

dictionary

Unchangeable types:

list

tuple

string

int

float

bool

LL[0] L[1] L[2]

Reference,Pointer,

id

L = [5,42,'hi']

x5 42 'hi'

42

x = 42

“Pass By Value”

def main() """ calls conform """ print " Welcome to Conformity, Inc. "

fav = 7 conform(fav)

print " My favorite number is", fav

def conform(fav) """ sets input to 42 """ fav = 42 return fav

7

fav

fav

7

“Pass By Value”

def main() """ calls conform """ print " Welcome to Conformity, Inc. "

fav = 7 conform(fav)

print " My favorite number is", fav

def conform(fav) """ sets input to 42 """ fav = 42 return fav

7

fav

fav

PASSBY VALUE

“Pass by value” means that data is copied when sent to a method

42

Passing lists by value…

def main() """ calls conform2 """ print " Welcome to Conformity, Inc. " fav = [ 7, 11 ] conform2(fav) print " My favorite numbers are", fav

def conform2(fav) """ sets all of fav to 42 """ fav[0] = 42 fav[1] = 42

What gets passed by value here?

favL[0] L[1]

5 42

fav

Passing lists by value…

def main() """ calls conform2 """ print " Welcome to Conformity, Inc. " fav = [ 7, 11 ] conform2(fav) print " My favorite numbers are", fav

def conform2(fav) """ sets all of fav to 42 """ fav[0] = 42 fav[1] = 42

favL[0] L[1]

5 42

fav

can change data

elsewhere!

The reference is copied!

The conclusion

You can change the contents of lists in functions that take those lists as input.

Those changes will be visible everywhere.

(actually, lists or any mutable objects)

(immutable objects are safe, however)

Views of the world

Engineers think their equations approximate reality.

Views of the world

Engineers think their equations approximate reality. Physicists think reality approximates their equations.

Views of the world

Engineers think their equations approximate reality. Physicists think reality approximates their equations.

Mathematicians don't care.

Views of the world

Axioms

Definitions

Creating structure from a few simple

facts...

Creating structure from a few simple

actions ...

if/else

while

for

arithmetic operations

variablesarrays

Proof Algorithm

Engineers think their equations approximate reality. Physicists think reality approximates their equations. Mathematicians don't care.

Lists’ flexibility

Lists can hold ANY type of dataA = [ 42., 75., 70. ] 42.0 75.0 70.0

float float floatlistA

they don’t have to be horizontal lists!

42.0

75.0

70.0

double

double

double

listAthey don’t

have to be horizontal lists!

Lists’ flexibility

Lists can hold ANY type of dataA = [ 42., 75., 70. ] 42.0 75.0 70.0

float float floatlistA

Lsits’ flexibility

Lists can hold ANY type of data

42.0 75.0 70.0double double doublelist

A

42 7 -11int int intlist

A

“go” “red” “sox!”

String String StringlistA

2d lists or arrays

Lists can hold ANY type of data -- including lists !

listA

A = [ [1,2,3,4], [5,6], [7,8,9,10,11] ]

listA

2d arrays

list

list

list

A[0]

A[1]

A[2]


A = [ [1,2,3,4], [5,6], [7,8,9,10,11] ]

listA

Jagged arrays

list

list

list

A[0]

A[1]

A[2]


A = [ [1,2,3,4], [5,6], [7,8,9,10,11] ]

Rows within 2d arrays need not be the same length…

listA

list

list

list

A[0]

A[1]

A[2]


A = [ [1,2,3,4], [5,6], [7,8,9,10,11] ]

Rows within 2d arrays need not be the same length…

We will not use jagged arrays

at least in hw 10

Rectangular arrays

listA

list

list

list

A[0]

A[1]

A[2]

How many rows does A have, in general ?How many columns does A have, in general ?

What does each component of A[1][2] mean ?

A[1][2] = 42

A[2][3]

A[0][0]

Creating a 2d array

def create2dArray( width, height ): """ does just that """

A = [] # start with nothing

for row in range( height ):

for col in range( width ):

return A

Displaying a 2d array

import csplot

B = create2dArray( 10, 10 )

csplot.show( B )

B[1][8] = 1 # set this item to 1

csplot.show( B )

Be sure to download the newest version of this file…

nearby coordinates…

Problem 2 -- “Life”

Evolutionary rules

Grid World

• Everything depends on a cell’s eight neighbors

red cells are alive

white cells are empty

• Exactly 3 neighbors give birth to a new, live cell!• Exactly 2 or 3 neighbors keep anexisting cell alive• Any other number of neighbors killthe central cell (or keep it dead)

John Conway

Problem 2 -- Life

Evolutionary rules

Grid World


red cells are alive



Problem 2 -- Life

Evolutionary rules

Grid World


red cells are alive



life out there...

Keep going!

Problem 2 -- Creating Life

0 1 2 3 4 50 1 2 3 4 5

0

1

2

3

4

5

0

1

2

3

4

5

B = update( B )

old generation or "board" new generation or "board"

Problem 2 -- Details

For each generation… • 0 represents an empty cell

• 1 represents a living cell

• outermost edge should always be left empty (even if there are 3 neighbors)

• compute all cells based on their previous neighbors before updating any of them

http://www.math.com/students/wonders/life/life.html

life out there...

B = update( B )

old generation or "board" new generation or "board"

Problem 2 -- to and beyond!

• Are there stable life configurations?

• Are there oscillating life configurations?

• Are there self-propagating life configurations?

"rocks"

"plants"

"animals"

period 3

period 2

Problem 2 -- to and beyond!

• Are there life configurations that expand forever?

• What is the largest amount of the life universe that can be filled with cells?

• How sophisticated can the structures in the life universe be?

Google for GOLLY, Game of Life

• Are all feasible configurations reachable?

Lab & Homework…

import sys

for i in range(4): for j in range(8): sys.stdout.write('#') print

software object representing the screen's standard output

Without extra spaces…

Output

################################

method (function) that prints only its input

IS 313 Today What's ahead? I see I'm not the only one loopy around here… 10/7 Lec 5 ~ today, now!...

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