FAQ

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Frequently asked questions about installing and using AsNumpy.

How do I check if CANN is correctly installed?

cat /usr/local/Ascend/ascend-toolkit/latest/version.cfg

What should I do if I encounter a compilation error?

Confirm CMake version >= 3.26: cmake --version
Confirm GCC version >= 11.2: gcc --version

Ensure the CANN environment variable is set:

export ASCEND_TOOLKIT_HOME=/usr/local/Ascend/ascend-toolkit/latest

Try a clean rebuild:
```
pip install -e . --no-build-isolation
```

How compatible is AsNumpy with NumPy?

AsNumpy is designed to be API-compatible with NumPy, but operator coverage is not yet complete. The current version (v0.2.0) covers the most common math, logic, sorting, and array-creation APIs.

The roadmap target is to cover the top 100 most-used NumPy APIs by v1.0. See the README roadmap for the full plan.

Why is AsNumpy slower than NumPy for small arrays?

For small tensors (e.g., 500×500), NPU kernel launch overhead dominates the measured time. NPU acceleration becomes significant starting around 1000×1000 (float32). See Benchmarks for detailed data.

Do I need to manually initialize or finalize the NPU?

No. AsNumpy handles device initialization automatically on import asnumpy and releases the device on program exit. You only need to call ap.set_device(n) if you want to select a specific NPU other than device 0.