Class 11 – Friday, February 8

In a loop, a loop — Nesting, but not like a bird — Repeating again

You did not expect – The repetition to come – You did not expect

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Look both ways

• Back or ahead

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Agenda

• Extend print() function functionality

• Introduce the time module

• Doing loop the loops

• Introduce the pillow.

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Problems

• Program thats_printastic.py

• Introduces the optional closing parameter end="..."

Wa-Hoo-Wa

Rah-Rah-Rah

Wa-Hoo-Wa!!!Rah-Rah-Rah

Wa-Hoo-Wa !!! Rah-Rah-Rah

t-a-t-t-a-r-r-a-t-t-a-t-

saippuakivikauppias

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• Program nested_looper.py

• Introduces nested looping. Where for a user-supplied n, the program loops n times and on the i^th iteration prints a line of the form

i: 0 1 2 ... i

• Two sample program runs

Enter number: 5

0: 0

1: 0 1

2: 0 1 2

3: 0 1 2 3

4: 0 1 2 3 4

Enter number: 12

0: 0

1: 0 1

2: 0 1 2

3: 0 1 2 3

4: 0 1 2 3 4

5: 0 1 2 3 4 5

6: 0 1 2 3 4 5 6

7: 0 1 2 3 4 5 6 7

8: 0 1 2 3 4 5 6 7 8

9: 0 1 2 3 4 5 6 7 8 9

10: 0 1 2 3 4 5 6 7 8 9 10

11: 0 1 2 3 4 5 6 7 8 9 10 11

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• Program vowely.py

• Gets a single word from the user and separately reports its length and its number of vowels

• Two sample program runs

Enter a word: subbookkeeper

length: 13

vowels: 66

Enter a word: supercalifragilisticexpialidocious

length: 34

vowels: 16

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• Program grabby.py

• Separately prompt for a string s and a list of integers numbers. The program displays the string formed by using numbers as indices into s.

• For example, suppose s equals 'abcdefghijklmnopqrstuvwxyz-' and numbers equals [ 4, 8, 26, 4, 8, 26, 14 ] the output is the string 'ei-ei-o', because s[ 4 ] equals 'e', s[ 8 ] equals 'i', s[ 14 ], equals 'o', and s[ 26 ] equals '-'. There should be no other output.

• Two sample program runs with preferred form of output

Enter string: computer

Enter list of indices: 5 1 7

tor

Enter string: gosh look what the cat is up to now

Enter list of indices: 24 5 17 17 27 23 32 0

sleeping

• Two sample program runs whose output form is acceptable for today

Enter string: computer

Enter list of indices: 5 1 7

t

o

r

Enter string: gosh look what the cat is up to now

Enter list of indices: 24 5 17 17 27 23 32 0

s

l

e

e

p

i

n

g

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To do list

• Install pillow.

• Reveal one of your super power(s)

• Share a selfie

• Review class artifacts.

• Complete the aeschylus.py homework by Monday 2PM.

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