Class 27 — October 25

Staying functional

I’m making a list – I’m not gonna check it twice – To find out if nice

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Look both ways

• Back or ahead

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Update

• UVA CS departmental submission server is now up

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Agenda

• Explore list manipulating methods

• Consider Python pass-by-value parameter implications (and some related implications)

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Best in show

• Fall 2017

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Module butter.py

• Defines three functions performing list manipulations.

• Function duplicate( x )

• Returns a new list whose elements are copies of those in x.

• Function is_inorder( x )

• Returns whether elements of x are in sorted order.

• Function greater( x, k )

• Returns a new list whose elements are those in x whose values are greater than k.

• Program bread.py performs simple testing of module butter.

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Module clean.py

• Defines three functions for cleaning up strings.

• Function lower( strings )

• Returns a new list whose elements are lower case versions of those in strings.

• Function strip( strings )

• Returns a new list whose elements correspond to the elements in strings with leading and trailing extraneous characters (punctuation or whitespace) removed.

• Function canonical( strings )

• Returns a new list whose elements are lower case versions of those in strings with leading and trailing extraneous characters removed.

• Program cleaning.py when augmented performs simple testing of module clean.

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To do

• Look over artifacts

• Homework

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