Vega-Lite重复折线图Y轴自定义计算问题求助

我在同一仪表盘中用repeat功能创建了3条折线图，当前Y轴直接显示p25/p50/p75的原始数值，无法修改为按(rank-1)*60计算的分桶位置值（data数组中每个数据点是步长60的分桶，p25/p50/p75对应data数组的百分位数）。

要实现需求，核心是把每个日期对应的p25/p50/p75值，匹配到其在对应data数组中的索引位置，再转换为分桶数值。以下是修改后的完整代码：

{
  "$schema": "https://vega.github.io/schema/vega-lite/v5.json",
  "data": {
    "values": [
      {"x":"22-05", "p25":0.375, "p50":1.65, "p75":9.875,"data":[0, 0.125, 0.375, 1.625, 9.875, 11.25, 12.5, 65.625]},
      {"x":"22-06", "p25":0.405, "p50":1.675, "p75":9.675,"data":[0, 0.125, 0.405, 1.675, 9.675, 12.25, 12.8, 66.4]},
      {"x":"22-07", "p25":0.355, "p50":2.3, "p75":11.25,"data":[0.2, 0.2, 0.355, 2.3, 9.3, 11.25, 12.5, 65.625]}
    ]
  },
  "transform": [
    // 计算每个百分位数在data数组中的索引，转换为分桶值（索引*60）
    {"calculate": "indexof(datum.data, datum.p25) * 60", "as": "buckets_p25"},
    {"calculate": "indexof(datum.data, datum.p50) * 60", "as": "buckets_p50"},
    {"calculate": "indexof(datum.data, datum.p75) * 60", "as": "buckets_p75"}
  ],
  "repeat": {"layer": ["buckets_p25", "buckets_p50", "buckets_p75"]},
  "spec": {
    "width":400,
    "mark": {"type":"line", "point":true},
    "encoding": {
      "x": {
        "field": "x", 
        "type": "nominal",  
        "title": "Dates",
        "axis":{"labelAngle":0, "titleFontSize":14,"titleFontWeight":700,"titleFont":"Google Sans" }
      },
      "y": {
        "field": {"repeat": "layer"},
        "title": "Bucket Position",
        "type": "quantitative"
      },
      "color": {
        "datum": {"repeat": "layer"}, 
        "scale":{"range":["blue","green","orange"]},
        "type": "nominal", 
        "legend":{"labelExpr":"datum.label =='buckets_p25'?'25th percentile':datum.label=='buckets_p50'?'50th percentile':'75th percentile'"}
      }
    }
  }
}

关键修改点： #

1. 简化数据转换：移除原代码中flatten和window计算rank的冗余步骤，直接用indexof函数定位百分位数在data数组中的位置，乘以60得到分桶值，生成对应的buckets_*字段。
2. 更新Repeat配置：将repeat的layer目标改为转换后的分桶字段，确保Y轴使用计算后的数值。
3. 优化轴与图例：补充Y轴标题，同时调整图例的表达式，匹配新的字段名称。

内容的提问来源于stack exchange，提问作者newDev