week2.md

revision

data types

- primitive: string, numbers(int and float), boolean(True, False)

operators

- arithmetic: +, -, /, *, ** , %
- boolean: and, or
- comparison: ==, <=, >=, !=

brief intro to function and return types

brief intro to control statements: if

agenda for today

immutable and mutable

lists

- list intro
- list operations: slicing, concatenation, append, len

if statement revisited

```python
    if <condition>:
        # execute something
    elif <condition2>:
        # execute something else
    else:
        # execute last resort/ goto option/ default behavior
```

loops

- while loop:
    - pairs best when there is no predefined number of iterations.

while <condition>:
    # do something
    # new condition arises
    # loop will terminate of re run

# example
from random import randint # we are using something from a package

possibilities = [True, True, False, True, False, False, True, True, True, False, True, True, True]
raoulJohnAndMarkusLunchTimeIsNotFree = possibilities[1]

while raoulJohnAndMarkusLunchTimeIsNotFree:
    print('Ask: (^o^)／ Oh hoy fellas, ready for coding buddies?')
    raoulJohnAndMarkusLunchTimeIsNotFree = possibilities[randint(0, possibilities.len() -1 )]
    if raoulJohnAndMarkusLunchTimeIsNotFree:
        print('(；一_一) Sorry man we have something far important than coding buddies.')
    else:
        print('ヽ(^。^)ノヽ(^o^)丿＼(^o^)／     ヽ(´ー｀)┌')

- for loop:
    - pairs best with lists or if something has finite number of iterations

days = [ 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday', 'Sunday' ]
moods = [
    'Arrgh. boy here we go again',
    'why is time so slow',
    'made it half way through',
    'yayy football. looking fwd to the weekend',
    'beer and pizza guys, beer and pizza',
    'this is going to be awesome weekend',
    'shit its almost over'
]

for day in days:
    print('today is ' + day)

for i in range(days.len()-1):
    print(moods[i] '. its ' + days[i])

break and continue

break breaks out of the current loop

whereas continue disregards the code flow that follows current iteration and continues with the loop

distances = ['here', 'there', 'sky', 'at moon', 'inifinity and beyond']

def skyIsTheLimit:
  for distance in distances:
    print('i\'m ' + distance)
    if distance == 'sky':
      print('sky is my limit')
      break

def skipMoon:
  for distance in distances:
    if distance == 'at moon':
      continue
    print('i\'m ' + distance)

tuples

• like lists but immutable

tuppleWare = ('some', 'random', 'collection')

functions

def functionName(arguments):
  # do function stuffs
  # return or not return