{
  "id": "python/pandas-groupby-agg-nonnumeric",
  "signature": "pandas.core.base.DataError: No numeric types to aggregate",
  "signature_zh": "pandas.core.base.DataError：没有可聚合的数值类型",
  "regex": "pandas\\.core\\.base\\.DataError:\\ No\\ numeric\\ types\\ to\\ aggregate",
  "domain": "python",
  "category": "data_error",
  "subcategory": null,
  "root_cause": "Groupby mean/sum applied to DataFrame with no numeric columns (all object/string).",
  "root_cause_type": "generic",
  "root_cause_zh": "对全为非数值列（object/字符串）的 DataFrame 执行 groupby mean/sum。",
  "versions": [
    {
      "version": "3.x",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    }
  ],
  "os_specific": {},
  "dead_ends": [
    {
      "action": "",
      "why_fails": "Returns empty frame when no numeric columns exist",
      "fail_rate": 0.7,
      "condition": "",
      "sources": []
    },
    {
      "action": "",
      "why_fails": "Fails on non-numeric strings",
      "fail_rate": 0.8,
      "condition": "",
      "sources": []
    }
  ],
  "workarounds": [
    {
      "action": "",
      "success_rate": 0.95,
      "how": "df.select_dtypes(include='number').groupby(key).mean()",
      "condition": "",
      "sources": []
    },
    {
      "action": "",
      "success_rate": 0.9,
      "how": "Convert target column first: df['val'] = pd.to_numeric(df['val'], errors='coerce')",
      "condition": "",
      "sources": []
    }
  ],
  "workarounds_zh": [],
  "transition_graph": {
    "leads_to": [],
    "preceded_by": [],
    "frequently_confused_with": []
  },
  "official_doc_url": null,
  "official_doc_section": null,
  "error_code": null,
  "verification_tier": "ai_generated",
  "confidence": 0.88,
  "fix_success_rate": 0.8,
  "resolvable": "true",
  "first_seen": "2024-12-03",
  "last_confirmed": "2025-01-01",
  "last_updated": "2025-01-01",
  "evidence_count": 0,
  "tags": [],
  "locale": "en",
  "aliases": []
}