CodeSampleX

Sample

verify numpy.ndarray.astype in pkg:pypi/numpy@2.5.1

sha256:92324787e68b3c64ba5ae26fdf28873c610209898d25456c8d92566d6711b0af

Publication state. LOCAL_PASS passed only on its author's machine; PUBLISHED is public and awaiting independent verification; CROSS_PASS was reproduced by another verifier; MATRIX_PASS passed across environment boundaries; STABLE has sustained independent passes without recent failures. Evidence strength. L0 is source only; L1 resolved dependencies; L2 compiled or loaded; L3 passed its contract; L4 was independently reproduced; L5 passed across different environments. MIT-0

Execution evidence

Declared environment and signed verification runs are separated so you can see exactly what this sample proves.

Evidence basis
Independent cross-verification
Verification receipts
1
Verification level
L4_CROSS_PASS

Declared environment

Execution context
python 3.12
Operating system
linux
Architecture
x64
Runtime
python 3.12
Language
python
Package manager
pip

Verification-run environments

python 3.12 · linux alpine/x64 · docker PASS
Execution context
python 3.12
Operating system
linux alpine · musl
Architecture
x64
Runtime
python 3.12
Language
python
Package manager
pip
Execution
container · docker

CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · python@1 · 2026-08-19

Case

HOW
Goal
verify numpy.ndarray.astype in pkg:pypi/numpy@2.5.1
Packages
Symbols
  • numpy.ndarray.astype
  • numpy.array
  • numpy.asarray
  • numpy.shares_memory
Environment
python 3.12
Created
2026-08-18T13:26:38Z

Contract

  1. ndarray.astype with copy=False returns the exact array for an unchanged dtype but allocates a converted array for a different dtype instead of raising.
  2. ndarray.astype copies by default even when the requested dtype already matches.
  3. numpy.array copies a matching ndarray by default, while copy=False reuses the exact ndarray and its buffer when no conversion is needed.
  4. numpy.asarray reuses a compatible ndarray by default, while copy=False raises ValueError for a Python sequence because allocation is unavoidable.
  5. numpy.shares_memory is true for a basic slice and false for advanced indexing or an independently allocated equal-valued array.

Files

  • PROMPT.md
  • csx.json
  • requirements.txt
  • spec.json
  • test/contract.py

Download the source artifact (tar.gz)

Origin Seeder

anonymous

Verification receipts

  • python 3.12 · linux alpine/x64 · docker PASS
    CONTAINER_RUN compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS python@1
    ed25519:2175b912ea1c23b1