Using iterators to load large files into memory

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Hugo Bowne-Anderson

Data Scientist at DataCamp

Loading data in chunks

There can be too much data to hold in memory
Solution: load data in chunks!
pandas function: read_csv()
- Specify the chunk: chunksize

Iterating over data

import pandas as pd
result = []

for chunk in pd.read_csv('data.csv', chunksize=1000):

    result.append(sum(chunk['x']))

total = sum(result)

print(total)

Iterating over data

import pandas as pd
total = 0

for chunk in pd.read_csv('data.csv', chunksize=1000):
    total += sum(chunk['x'])

print(total)

Let's practice!

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