What is array flattening in NumPy?

Updated May 17, 2026

Short answer

Flattening converts multi-dimensional arrays into 1D arrays.

Deep explanation

flatten returns a copy while ravel returns a view when possible, affecting memory usage and performance.

Real-world example

Preparing data for machine learning models.

Common mistakes

  • Assuming flatten and ravel behave identically.

Follow-up questions

  • Which is faster, flatten or ravel?
  • Does flatten modify original array?

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