--- id: python-memoryview title: "Python Memoryview" category: "Programming_Language" status: "draft" verification_status: "conceptual" canonical_id: "" aliases: ["memoryview type", "파이썬 메모리뷰"] duplicate_of: "" source_trust_level: "B" confidence_score: 0.85 created_at: 2026-07-04 updated_at: 2026-07-04 review_reason: "" merge_history: [] tags: ["python", "programming", "w3schools", "memoryview", "binary"] raw_sources: ["https://www.w3schools.com/python/python_memoryview.asp"] applied_in: [] github_commit: "" --- # [[Python Memoryview]] ## 🎯 한 줄 통찰 (One-line insight) memoryview exposes a buffer-protocol object's raw data without copying it — slicing and, if the underlying object is mutable, writing through the view directly modifies the original buffer. [S1] ## 🧠 핵심 개념 (Core concepts) - **memoryview** — a Python-level view of an object's internal data (any object supporting the buffer protocol, like bytes/bytearray), without copying. [S1] - **Creation** — wrap a bytes-like object with `memoryview()`. [S1] - **Zero-copy access** — reading/slicing accesses the underlying buffer directly. [S1] - **Write-through (mutable underlying object)** — assigning through the memoryview modifies the original bytearray in place. [S1] - **`.tobytes()`** — converts a view (or slice of it) into an actual bytes copy. [S1] ## 🧩 추출된 패턴 (Extracted patterns) - **View vs. copy distinction** — a memoryview is a lens onto existing memory, not a new object; `.tobytes()` is the explicit boundary where you opt into copying. [S1] ## 📖 세부 내용 (Details) - Create from bytes: `x = memoryview(bytes(5)); print(type(x))`. [S1] - Slice and write-through on a mutable buffer: `b = bytearray(b"abcdef"); v = memoryview(b); print(v[1:4].tobytes()) # b'bcd'; v[0] = ord('Z'); print(b) # bytearray(b"Zbcdef")`. [S1] ## ⚖️ 모순 및 업데이트 (Contradictions & updates) 소스에서 모순되는 정보는 발견되지 않음. ## 🛠️ 적용 사례 (Applied in summary) 현재 발견된 실제 적용 사례가 없습니다 — 대용량 바이너리 데이터를 복사 없이 다뤄야 하는 성능 민감 상황에서 쓰이는 개념이다. [S1] ## 💻 코드 패턴 (Code patterns) Write-through a mutable buffer via memoryview (Python): ```python b = bytearray(b"abcdef") v = memoryview(b) v[0] = ord('Z') print(b) # bytearray(b"Zbcdef") ``` ## ✅ 검증 상태 및 신뢰도 - **상태:** draft - **검증 단계:** conceptual - **출처 신뢰도:** B (W3Schools — widely used educational reference, not a primary standards body) - **신뢰 점수:** 0.85 - **중복 검사 결과:** 신규 생성 (New discovery) ## 🔗 지식 그래프 (Knowledge Graph) - **상위/루트:** [[Python Tutorial]] - **관련 개념:** [[Python Bytes]], [[Python Bytearray]] - **참조 맥락:** 복사 없이 바이너리 버퍼를 조회·수정해야 하는 성능 민감 상황에서 사용. ## 📚 출처 (Sources) - [S1] W3Schools — Python memoryview — https://www.w3schools.com/python/python_memoryview.asp ## 📝 변경 이력 (Change history) - 2026-07-04: Initial draft synthesized from the W3Schools "Python memoryview" page (Astra wiki-curation, P-Reinforce v3.1 format).