# 错误：无效的依赖项：'numpy>=1.19.0,<2.0'

- **ID:** `python/pip-invalid-requirement-package-name`
- **领域:** python
- **类别:** config_error
- **验证级别:** ai_generated
- **修复率:** 80%

## 根因

由于语法错误（例如缺少引号、多余空格），pip无法解析依赖项字符串。

## 版本兼容性

| 版本 | 状态 | 引入 | 弃用 |
|------|------|------|------|
| 3.9 | active | — | — |

## 解决方案

1. **Use proper requirement format with quotes** (95% 成功率)
   ```
   pip install 'numpy>=1.19.0,<2.0'
   ```
2. **Specify in requirements.txt correctly** (90% 成功率)
   ```
   echo 'numpy>=1.19.0,<2.0' >> requirements.txt
pip install -r requirements.txt
   ```

## 无效尝试

- **Removing version specifiers entirely** — Loses version constraints; may install incompatible version. (70% 失败率)
- **Using semicolon instead of comma** — Pip uses commas for multiple constraints; semicolon is invalid. (90% 失败率)