{
  "$schema": "https://vega.github.io/schema/vega/v5.json",
  "background": "white",
  "padding": 5,
  "width": 20,
  "style": "cell",
  "data": [
    {
      "name": "source_0",
      "values": [
        {"a": "A", "b": 28},
        {"a": "B", "b": 55},
        {"a": "C", "b": 43},
        {"a": "D", "b": 91},
        {"a": "E", "b": 81},
        {"a": "F", "b": 53},
        {"a": "G", "b": 19},
        {"a": "H", "b": 87},
        {"a": "I", "b": 52}
      ]
    },
    {
      "name": "data_0",
      "source": "source_0",
      "transform": [
        {
          "type": "filter",
          "expr": "isValid(datum[\"b\"]) && isFinite(+datum[\"b\"])"
        }
      ]
    }
  ],
  "signals": [
    {"name": "y_step", "value": 20},
    {
      "name": "height",
      "update": "bandspace(domain('y').length, 1, 0.5) * y_step"
    }
  ],
  "marks": [
    {
      "name": "marks",
      "type": "symbol",
      "style": ["circle"],
      "from": {"data": "data_0"},
      "encode": {
        "update": {
          "opacity": {"value": 0.7},
          "fill": {"scale": "color", "field": "b"},
          "ariaRoleDescription": {"value": "circle"},
          "description": {
            "signal": "\"b: \" + (isValid(datum[\"b\"]) ? datum[\"b\"] : \"\"+datum[\"b\"])"
          },
          "x": {"signal": "width", "mult": 0.5},
          "y": {"scale": "y", "field": "b"},
          "size": {"scale": "size", "field": "b"},
          "shape": {"value": "circle"}
        }
      }
    }
  ],
  "scales": [
    {
      "name": "y",
      "type": "point",
      "domain": {"data": "data_0", "field": "b"},
      "range": {"step": {"signal": "y_step"}},
      "padding": 0.5
    },
    {
      "name": "color",
      "type": "threshold",
      "domain": [30, 70],
      "range": {"scheme": "viridis"},
      "interpolate": "hcl"
    },
    {
      "name": "size",
      "type": "threshold",
      "domain": [30, 70],
      "range": [80, 200, 320]
    }
  ],
  "axes": [
    {
      "scale": "y",
      "orient": "left",
      "grid": false,
      "domain": false,
      "ticks": false,
      "zindex": 0
    }
  ],
  "legends": [
    {
      "title": "Threshold",
      "fill": "color",
      "labelOverlap": "greedy",
      "symbolType": "circle",
      "encode": {"symbols": {"update": {"opacity": {"value": 0.7}}}},
      "size": "size"
    }
  ]
}