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pythonintermediate

Pandas .eval() for Fast Column Computation

Use DataFrame.eval() for expressive, fast in-place column calculations using numexpr.

python
import pandas as pd, numpy as np

df = pd.DataFrame(np.random.rand(1_000_000, 3), columns=['A','B','C'])

df.eval('D = A * 2 + B - C', inplace=True)
df.eval("""
    E = D ** 2
    F = A + C
""", inplace=True)
print(df.describe())

Use Cases

  • large DataFrame operations
  • formula evaluation
  • performance optimization

Tags

#pandas#eval#performance#numexpr

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