---
id: python-user-input
title: "Python User Input"
category: "Programming_Language"
status: "draft"
verification_status: "conceptual"
canonical_id: ""
aliases: ["input()", "파이썬 사용자 입력"]
duplicate_of: ""
source_trust_level: "B"
confidence_score: 0.9
created_at: 2026-07-04
updated_at: 2026-07-04
review_reason: ""
merge_history: []
tags: ["python", "programming", "w3schools", "input", "validation"]
raw_sources: ["https://www.w3schools.com/python/python_user_input.asp"]
applied_in: []
github_commit: ""
---

# [[Python User Input]]

## 🎯 한 줄 통찰 (One-line insight)
input() always returns a string regardless of what the user types — a numeric-looking input still needs float()/int() conversion, and a while-loop-with-try-except is the standard pattern to keep re-prompting until the conversion succeeds. [S1]

## 🧠 핵심 개념 (Core concepts)
- **`input()`** — pauses execution, waits for user input, returns it as a string. [S1]
- **Prompt parameter** — `input("Enter your name:")` puts a message before the input on the same line. [S1]
- **Multiple inputs** — each `input()` call blocks separately, in sequence. [S1]
- **Input is always a string** — even numeric-looking input must be converted with `float()`/`int()`. [S1]
- **Validation loop pattern** — combine a `while` loop with `try`/`except` to keep re-prompting until valid input is given. [S1]

## 🧩 추출된 패턴 (Extracted patterns)
- **The retry-until-valid idiom** — `while y == True: x = input(...); try: x = float(x); y = False except: print("Wrong input, please try again.")` is the canonical pattern combining [[Python Try Except]] and [[Python While Loops]] to build robust input validation. [S1]

## 📖 세부 내용 (Details)
- Basic input: `print("Enter your name:"); name = input(); print(f"Hello {name}")`. [S1]
- Prompt parameter: `name = input("Enter your name:")`. [S1]
- Convert to number: `x = input("Enter a number:"); y = math.sqrt(float(x))`. [S1]
- Validation loop: [S1]
```python
y = True
while y == True:
    x = input("Enter a number:")
    try:
        x = float(x)
        y = False
    except:
        print("Wrong input, please try again.")
print("Thank you!")
```

## ⚖️ 모순 및 업데이트 (Contradictions & updates)
소스에서 모순되는 정보는 발견되지 않음.

## 🛠️ 적용 사례 (Applied in summary)
현재 발견된 실제 적용 사례가 없습니다 — Try Except와 While Loops를 결합한 입력 검증 루프는 실무 CLI 도구의 표준 패턴이다. [S1]

## 💻 코드 패턴 (Code patterns)
Retry-until-valid input loop (Python):
```python
y = True
while y == True:
    x = input("Enter a number:")
    try:
        x = float(x)
        y = False
    except:
        print("Wrong input, please try again.")
```

## ✅ 검증 상태 및 신뢰도
- **상태:** draft
- **검증 단계:** conceptual
- **출처 신뢰도:** B (W3Schools — widely used educational reference, not a primary standards body)
- **신뢰 점수:** 0.90
- **중복 검사 결과:** 신규 생성 (New discovery)

## 🔗 지식 그래프 (Knowledge Graph)
- **상위/루트:** [[Python Tutorial]]
- **관련 개념:** [[Python Try Except]], [[Python While Loops]], [[Python Casting]]
- **참조 맥락:** 사용자 입력 처리의 기본 — Try Except/While Loops와 결합해 견고한 검증 루프를 만든다.

## 📚 출처 (Sources)
- [S1] W3Schools — Python User Input — https://www.w3schools.com/python/python_user_input.asp

## 📝 변경 이력 (Change history)
- 2026-07-04: Initial draft synthesized from the W3Schools "Python User Input" page (Astra wiki-curation, P-Reinforce v3.1 format).
