For Loops 2024 Nov 9

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# WEBINAR: For Loops
2024 Nov 9

# We use loops to repeat actions
# a WHILE loop... is an IF that repeats as long as the loop condition remains True
#
# FOR LOOPS are used for repeating actions for every element in a container (list, dict, tuple, str, range, etc)

# Basic syntax of a for loop
# for ___ in _someContainer_:

# For Loop variables (the word after the for keyword) are SPECIAL VARIABLES that come along with this loop

# LIST
myList = ["Agent Scully", "Agent Mulder", "Walter Skinner", "CSM", "Mr. X"]
# for item in myList:
#     print(item)
#
# # TUPLE
# myTuple = ("Gilligan", "Castaway002", "red", "crew")
# for item in myTuple:
#     print(item)
#
# # STRING
# myStr = "It was the best of times."
# for char in myStr:
#     print(char)

# DICT
# myDict = {
#     key: value,
#     key: value,
#     key: value
# }
# myDict[key] # get the value for that key
# myDict[key] = value # assign value to key

# for ___ in myDict: # what does the loop var hold when looping over a dict?

bestOfXF = {
    "1x00": "Pilot",
    "2x10": "Red Museum",
    "2x14": "Die Hand Die Verletzt",
    "3x04": "Clyde Bruckman's Final Repose",
    "3x12": "War of the Coprophages",
    "3x20": "Jose Chung's From Outer Space",
    "4x05": "The Field Where I Died",
    "5x05": "The Post Modern Prometheus",
    "5x17": "All Souls"
}
# for ___ in thisDict:
# for key in bestOfXF:
#     # print(key)
#     # print(bestOfXF[key])
#     # "Check out Episode ___ or '---'."
#     print(f"Check out Episode {key} or '{bestOfXF[key]}'")

# Loop a known of number of times
# RANGE
# range(start=0, stop, step=1)
# range(5) # range(0, 5, 1) --> [0, 1, 2, 3, 4]
# for num in range(5):
#     print(num)

# Looping over a container and I need to know the index
# RANGE of LEN
myList.append("Kyrcek")
# for i in range(len(myList)):
#     # print(i)
#     # print(myList[i])
#     print(f"{i}: {myList[i]}")

# ENUMERATE
# for i, item in enumerate(myList):
#     print(f"{i} --> {item}")

# FILL THE BASKET / FILTER
agentList = [] # start a new container
for item in myList:
    # filter with an if
    if "Agent" in item:
        agentList.append(item)
print(agentList)

# comprehension
# A comprehension is just a condensed way of doing the "for loop to fill one container based on another" that we just did above
# (I rarely use them)

agentList = [item for item in myList if "Agent" in item]
print(agentList)

strNums = ["1", "3", "24"]
numList = [int(num) for num in strNums]
for num in strNums:
    numList.append(int(num))
print(numList)

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