webinar-for-loops-2021-09-11

# WEBINAR: For Loops
# We use loops to repeat actions

# a WHILE loop is basically an IF statement
# that repeats as long as its condition is true

# FOR LOOPS are used for repeating actions for every element
# in a container like a list, string, tuple, etc...

# Focus on FOR LOOPS for the OA (don't worry about while loops so much)
# Don't worry about nested loops either :), just one loop at a time

# BASIC LOOP syntax with a list
# for __ in ___:
# for _myVar_ in _someContainer_:
myList = ["Agent Scully", "Agent Mulder", "Walter Skinner", "CSM", "Mr. X"] # X-Files characters
for item in myList:
    print(item)

# tuple
myTuple = ("Gilligan", "Castaway002", "red", "crew") # things about Gilligan
for item in myTuple:
    print(item)

myString = "Just sit right back and you'll hear a tale."
# for char in myString:
#   print(char)

# dict
scoobiesDCT = {
    "Scooby": "a blue collar",
    "Shaggy": "green",
    "Velma": "orange",
    "Daphne": "purple",
    "Fred": "an ascot"
}
# nameOfDict[key] = value
for key in scoobiesDCT:
    v = scoobiesDCT[key]
    print(key, "-->", v)

# range() turns numbers into an iterable container
for n in range(0, 5): # integers aren't iterable, but range objects are
    print(n)

# Getting the index of a list or other container's values
# 2 ways to do this...
# range() + len()
for i in range(len(myList)):
    item = myList[i]
    print(i, ":", myList[i])
# enumerate()
for i, item in enumerate(myList):
    print(i, ">>", item)


# examples and student questions...
# Ch 8 Task 10
# Complete the function to return the number of upper case letters in the given string
def countUpper(mystring):
    # string method isupper()
    count = 0
    for letter in mystring:
        if letter.isupper():
            # print(letter)
            count += 1
    return count

print(countUpper('Welcome to WGU'))# expected output: 4
print(countUpper('Hello Mary'))# expected output: 2

# using help() or dir() in test system
def myFunction(x, y, z):
    # help(str)
    h = help(str)
    return h
    # return x + y + z

print(myFunction(1, 2, 3))
print(myFunction(4, 5, 6))

# Ch 12 Task 5
import os
# Complete the function to print all files in the given directory
def printFiles(someDirectory):
    # return os.listdir(someDirectory) # wrong! b/c that's a list
    # fileList = os.listdir(someDirectory)
    for item in os.listdir(someDirectory):
        print(item)

# expected output: main.py # <--- ALWAYS watch the output! It's not a list!
printFiles(os.getcwd())