Class 41 — November 29

I know that

Programming basics — You achieved this semester — Bask in the success

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Look both ways

• Back or ahead

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Download if needed

• do.py

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Survey

• Please look at it

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Agenda

• Discuss algorithmic patterns

• Continue coloring

• Consider Beyonce on the UVA Lawn

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Important patterns

• Print output

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• Get input

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• Convert input to data

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• Perform calculations

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• Process strings

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• Get web input

• Use to do above and below tasks

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• Examine and create lists

• Convert a string into a list of strings

• Convert a list of strings into a list of numbers

• Perform an accumulation

• Check to see if the elements of the list are all of the same form

• Check to see if any element of the list has a desired form.

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• Generate random data

• Produce random value from a range

• Produce random from a list

• Produce a random tuple

• Produce random lists and tables

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• CSV data

• Convert a list of CSV-strings into a new list of lists

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• Examine and create dictionaries

• Convert a list of tuples into a dictionary

• Convert a list of two-element lists into a dictionary

• Examine a list with respect to a dictionary

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• Examine a table

• Perform an accumulation

• Process a table on a row by row basis

• Convert cells from strings to numerics

• Check to see if all data cells in the table are of the same form

• Check to see if any data cells in the table are of the desired form

• Check to see if all rows in the table are of the same form

• Check to see if any rows in the table are of the desired form

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• Design, implement, analyze functions that can encapsulate the above tasks

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• Photo manipulation

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Realizations

• A variable has an identity and a type

• The value of a variable indicates where the object which it represents can be found

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• Strings are immutable

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• String functions require the use of a parameters

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• String splitting

• s.strip() returns a new list of the words making up s.

• s.strip( '\n' ) returns a new list of the lines making up s.

• s.strip( ',' ) returns a new list of the comma-separated data cells making up s.

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• Converting string data to numeric data.

• To hand back a single integer value nbr from a single numeric representation v

nbr = int( v )

• To hand back a list of integer values nbrs from a string list strings

nbrs = []

for v in s :

nbr = int( v )

nbrs.append( nbr )

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• A function invocation cannot change the identity of an argument

• All functions return a value either explicitly or implicitly. If there is no explicit return, None is returned.

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To do

• Review for Monday

• Complete Homework 28