03-5-python-filtering.md

Data 3-5: Python - Filtering

We can use for loops and if statements to filter through data.

rows = [
    {"name": "Rachel", "age": 34},
    {"name": "Monica", "age": 34},
    {"name": "Phoebe", "age": 37}
]

# filter to age < 37
millenials = []
for row in rows:
    if row['age'] < 37:
        millenials.append(row)

print(millenials)

# filter whitelist names

cool_people = []
whitelist = ['Rachel', 'Phoebe']
for row in rows:
    if row['name'] in whitelist:
        cool_people.append(row)

print(cool_people)

# filter blacklist names

cool_people = []
blacklist = ['Monica']
for row in rows:
    if row['name'] not in blacklist:
        cool_people.append(row)

print(cool_people)

If you use Python's Pandas library for data manipulation and analysis instead, the code would look like this: https://gist.github.com/AlJohri/59c9762845519f999eb28fe45276f4c1

➡️ Try It

1. Read output/vegetables.csv into a variable called vegetables.
2. Loop through vegetables and filter down to only green vegtables using a whitelist.
3. Print veggies to the terminal
4. Write the veggies to a json file called output/greenveggies.json

Bonus: Output another csv called output/green_vegetables.csv.