bar_grouped_step_for_offset.vg.json

{
  "$schema": "https://vega.github.io/schema/vega/v5.json",
  "background": "white",
  "padding": 5,
  "height": 200,
  "style": "cell",
  "data": [
    {
      "name": "source_0",
      "values": [
        {"category": "A", "group": "x", "value": 0.1},
        {"category": "A", "group": "y", "value": 0.6},
        {"category": "A", "group": "z", "value": 0.9},
        {"category": "B", "group": "x", "value": 0.7},
        {"category": "B", "group": "y", "value": 0.2},
        {"category": "B", "group": "z", "value": 1.1},
        {"category": "C", "group": "x", "value": 0.6},
        {"category": "C", "group": "y", "value": 0.1},
        {"category": "C", "group": "z", "value": 0.2}
      ]
    },
    {
      "name": "data_0",
      "source": "source_0",
      "transform": [
        {
          "type": "stack",
          "groupby": ["category", "group"],
          "field": "value",
          "sort": {"field": [], "order": []},
          "as": ["value_start", "value_end"],
          "offset": "zero"
        },
        {
          "type": "filter",
          "expr": "isValid(datum[\"value\"]) && isFinite(+datum[\"value\"])"
        }
      ]
    }
  ],
  "signals": [
    {
      "name": "x_step",
      "update": "24 * bandspace(domain('xOffset').length, 0, 0) / (1-0.2)"
    },
    {
      "name": "width",
      "update": "bandspace(domain('x').length, 0.2, 0.2) * x_step"
    }
  ],
  "marks": [
    {
      "name": "marks",
      "type": "rect",
      "style": ["bar"],
      "from": {"data": "data_0"},
      "encode": {
        "update": {
          "fill": {"scale": "color", "field": "group"},
          "ariaRoleDescription": {"value": "bar"},
          "description": {
            "signal": "\"category: \" + (isValid(datum[\"category\"]) ? datum[\"category\"] : \"\"+datum[\"category\"]) + \"; value: \" + (format(datum[\"value\"], \"\")) + \"; group: \" + (isValid(datum[\"group\"]) ? datum[\"group\"] : \"\"+datum[\"group\"])"
          },
          "x": {
            "scale": "x",
            "field": "category",
            "offset": {"scale": "xOffset", "field": "group"}
          },
          "width": {"signal": "max(0.25, bandwidth('xOffset'))"},
          "y": {"scale": "y", "field": "value_end"},
          "y2": {"scale": "y", "field": "value_start"}
        }
      }
    }
  ],
  "scales": [
    {
      "name": "x",
      "type": "band",
      "domain": {"data": "data_0", "field": "category", "sort": true},
      "range": {"step": {"signal": "x_step"}},
      "paddingInner": 0.2,
      "paddingOuter": 0.2
    },
    {
      "name": "y",
      "type": "linear",
      "domain": {"data": "data_0", "fields": ["value_start", "value_end"]},
      "range": [{"signal": "height"}, 0],
      "nice": true,
      "zero": true
    },
    {
      "name": "xOffset",
      "type": "band",
      "domain": {"data": "data_0", "field": "group", "sort": true},
      "range": {"step": 24}
    },
    {
      "name": "color",
      "type": "ordinal",
      "domain": {"data": "data_0", "field": "group", "sort": true},
      "range": "category"
    }
  ],
  "axes": [
    {
      "scale": "x",
      "orient": "bottom",
      "grid": false,
      "title": "category",
      "labelAlign": "right",
      "labelAngle": 270,
      "labelBaseline": "middle",
      "zindex": 0
    },
    {
      "scale": "y",
      "orient": "left",
      "grid": false,
      "title": "population",
      "labelOverlap": true,
      "tickCount": {"signal": "ceil(height/40)"},
      "zindex": 0
    }
  ],
  "legends": [{"fill": "color", "symbolType": "square", "title": "group"}]
}