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dongdiri
dongdiri

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DAY18: Python day 26

Python list comprehension

  • very unique to Python
  • an alternative to a for loop when working with sequences like list, range, string, tuple
  • new_list = [new_item for item in list] 
numbers = [1, 2, 3]
new_list = [n+1 for n in numbers]

name = "dongdiri"
character_list = [letter for letter in name]
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  • also can add an if statement 
character_list = [letter for letter in name if character != "r"
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Dictionary comprehension

  • new_dict = {new_key:new_value for item in list} or {new_key:new_value for (key, value) in dict.items()}
  • be careful not to forget .items()

Panda .iterrows

  • loop through rows of a data frame using panda 
{row.new_key:row.new_value for (index, row) in data.iterrows()}
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End of the lesson project: NATO alphabet converter

#TODO 1. Create a dictionary in this format:
data = pandas.read_csv("nato_phonetic_alphabet.csv")
new_dict = {row.letter: row.code for (index, row) in data.iterrows()}

#TODO 2. Create a list of the phonetic code words from a word that the user inputs.
name = input("enter a word: ").upper()
code_list = [new_dict[letter] for letter in name]
print(code_list)
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Today's content was a bit hard to understand-I should take time to review it as well as python dictionaries.

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