Class 22 — Friday October 15

It's a fact, look it up

Really need to know — What lies farther down the road — Need a future map

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Look both ways

• Back or ahead

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Agenda

• hacer 뭔가 frais oggi

• Get ready to move on

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Examples

• Problem what_did_you_say.py

• Problem spell_rite.py

• Problem wc.py

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To do

• Look over artifacts

• Do homework

• Submit program spell_rite.py today

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Huh?

• dónde está mi lápiz

• donde esta mi lapiz

• hvor 是 该 tumili maleri av Munch

• est la baguette fraîche aujourd'hui

• est la baguette fraiche aujourd'hui

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Babelfish — a translation dictionary in CSV format

a, a

aab, water

aamadam, came

...

ziba, beautiful

zur, to

zu, to

zwei, two

...

 

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Problem text translation using babelfish dictionary

• Goal

• Produce a program using translate text to English.

• Some possible interactions

Enter phrase to be translated: dónde está mi lápiz

where is my pencil

Enter phrase to be translated: est la baguette fraîche aujourd'hui

is the baguatte fresh today

Enter phrase to be translated: je %#@#&# ból svayam !

I _%#@#&#_ hurt myself !

Enter phrase to be translated: hvor er den skriget maleri af Munch

where is the scream painting by Münch

Enter phrase to be translated: hacer 뭔가 frais oggi

do something cool today

• Brainstorming

• How should we represent the translations?

• How should we represent the input?

• How should we represent the result?

• Discussion and requirements

• Important data structures that the program needs to accomplish its task.

• List of words making up the user text.

• Dictionary loaded with the entries from the babelfish web file.

• Translation accumulation.

• If a word to be translated is not in the translation dictionary, then its translation is that word surrounded by underscores (_).

• For example, French word heureuse for happiness is not in the babelfish dictionary, so it would be translated as _heureuse_.

• The translation should be displayed with a single print() statement.

• The translation needs to be stored as a string.

• The translation of the user text needs to be accumulated word by word.

• We need a string accumulator.

• When accumulating the translation, need a space following each word to separate it from the next word.

• To produce the accumulation, each word in the user-supplied text needs to be processed one by one.

• Every user word contributes to the translation.

• If a word is known to the babelish dictionary, its translation is added to the accumulation.

• If instead a word is unknown, the word surrounded by underscores is added to the accumulation.

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Spell correction — program spell_rite.py

• Web resources

• most-common — list of most commonly used words

• corrections — list of most common misspellings and their likely correction

• Goal

• Produce a spell-checked version of user text that echos the user text word by word, unless a word is not known to be spelled correctly

• If a correction is known, the correction is offered within asterisks.

• If instead no correction is known, the word is flagged with underscores.

• Some possible program interactions

Enter text: I am as happy as I can be

I am as happy as I can be

Enter text: I am a Newyorker who is livin in virginia

I am a *New Yorker* who is _livin_ in *Virginia*

Enter text:

 

• Brain storming

• Problem has great similarity with text translation.

• If a word is spelled correctly, then it is added to the accumulation.

• If instead a word has an unknown spelling, then if it is known to the corrections dictionary then the correction surrounded by asterisks is added to the accumulation.

• Otherwise, if a word has an unknown spelling and is unknown to the corrections dictionary, then the word surrounded by underscores is added to the accumulation.

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Program wc.py — making a point about the importance of functions

• What it does

• Determines the number of lines, words, and characters in a user-specified web file

• How it does it

• Uses built-in, string and list manipulating functions

• Imports a modules to gain access to its functions

• Some program runs

Enter web file link: http://www.cs1112.org

nl = 241

nw = 1261

nc = 14104

Enter web file link: http://www.nytimes.com

nl = 583

nw = 12339

nc = 1166144

• Code

# import module for internet access

import url

# get the lines of text from a user-specified file

reply = input( 'Enter web file link: ' )

link = reply.strip()

contents = url.get_contents( link )

# count the number of lines, words, and characters in the contents

nbr_lines = contents.count( '\n' )

words = contents.split()

nbr_words = len( words )

nbc_chars = len( contents )

# display result

print( 'nl =', nbr_lines )

print( 'nw =', nbr_words )

print( 'nc =', nbc_chars )

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Here we go

• Question: Why bother with functions?

• Makes problem solving possible. Without them you would need to figure out

• How to communicate with your keyboard to read what it’s being typed

• How to communicate to your display so that information can be displayed

• How to specify the range of integers a for statement uses to loop.

• How to ...

• Question: What built-in functions are missing — how should Python be updated?

• The url.py module is an attempt by me to let you skip the tedious web processing setup to do something interesting

• One of your classmates asked whether there was some function ints() that would handle a string containing a bunch of integers.

• We will get to that likely in another three classes or so.

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Babelfish — Hitchhiker's Guide to the Galaxy

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Ziggurat of Ur

 

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