What is stacking in NumPy?

Updated May 17, 2026

Short answer

Stacking combines multiple arrays into one along a new axis.

Deep explanation

Functions like vstack and hstack merge arrays vertically or horizontally, useful in dataset construction.

Real-world example

Combining batches of training data.

Common mistakes

  • Mismatched dimensions during stacking.

Follow-up questions

  • Difference between stack and concatenate?
  • What is axis in stacking?

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