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  3. Master Data Science with Python

Lesson 19 of 60 · python

Reading Data: CSV, Excel, JSON, and More

Duration: 20 minutes

Reading Data into Pandas

In practice, data lives in files, databases, or APIs. Pandas can ingest many formats.

CSV files

df_csv = pd.read_csv('data/sales.csv')
print(df_csv.head())

Excel files

df_excel = pd.read_excel('data/financials.xlsx', sheet_name='2023')
print(df_excel.shape)

JSON files

import json
with open('data/users.json') as f:
    data = json.load(f)

df_json = pd.json_normalize(data)
print(df_json.head())

Reading from a URL

titanic_url = "https://raw.githubusercontent.com/datasciencedojo/datasets/master/titanic.csv"
df_titanic = pd.read_csv(titanic_url)
print(df_titanic.shape)

Parameters to control parsing

  • sep: column delimiter
  • parse_dates: column(s) to parse as datetime
  • usecols: subset of columns to read
  • dtype: enforce column types
df = pd.read_csv('data/sample.csv', sep=';', parse_dates=['date'], dtype={'id': int})

Info

Large CSVs can be loaded in chunks with chunksize to avoid memory overflow.

Previous: DataFrames: Tabular Data in PandasNext: Writing Data: Exporting DataFrames