area_overlay_with_y2.vg.json

{
  "$schema": "https://vega.github.io/schema/vega/v5.json",
  "description": "Google's stock price over time.",
  "background": "white",
  "padding": 5,
  "width": 200,
  "height": 200,
  "style": "cell",
  "data": [
    {
      "name": "source_0",
      "url": "data/stocks.csv",
      "format": {"type": "csv", "parse": {"date": "date"}},
      "transform": [{"type": "filter", "expr": "datum.symbol==='GOOG'"}]
    },
    {
      "name": "data_0",
      "source": "source_0",
      "transform": [
        {
          "type": "filter",
          "expr": "(isDate(datum[\"date\"]) || (isValid(datum[\"date\"]) && isFinite(+datum[\"date\"]))) && isValid(datum[\"price\"]) && isFinite(+datum[\"price\"])"
        }
      ]
    }
  ],
  "marks": [
    {
      "name": "layer_0_marks",
      "type": "area",
      "style": ["area"],
      "sort": {"field": "datum[\"date\"]"},
      "from": {"data": "source_0"},
      "encode": {
        "update": {
          "opacity": {"value": 0.7},
          "orient": {"value": "vertical"},
          "fill": {"value": "#4c78a8"},
          "description": {
            "signal": "\"date: \" + (timeFormat(datum[\"date\"], '%b %d, %Y')) + \"; price: \" + (format(datum[\"price\"], \"\"))"
          },
          "x": {"scale": "x", "field": "date"},
          "y": {"scale": "y", "field": "price"},
          "y2": {"scale": "y", "value": 0},
          "defined": {
            "signal": "isValid(datum[\"date\"]) && isFinite(+datum[\"date\"]) && isValid(datum[\"price\"]) && isFinite(+datum[\"price\"])"
          }
        }
      }
    },
    {
      "name": "layer_1_marks",
      "type": "line",
      "style": ["line"],
      "sort": {"field": "datum[\"date\"]"},
      "from": {"data": "source_0"},
      "encode": {
        "update": {
          "stroke": {"value": "#4c78a8"},
          "description": {
            "signal": "\"date: \" + (timeFormat(datum[\"date\"], '%b %d, %Y')) + \"; price: \" + (format(datum[\"price\"], \"\"))"
          },
          "x": {"scale": "x", "field": "date"},
          "y": {"scale": "y", "field": "price"},
          "defined": {
            "signal": "isValid(datum[\"date\"]) && isFinite(+datum[\"date\"]) && isValid(datum[\"price\"]) && isFinite(+datum[\"price\"])"
          }
        }
      }
    },
    {
      "name": "layer_2_marks",
      "type": "symbol",
      "style": ["point"],
      "from": {"data": "data_0"},
      "encode": {
        "update": {
          "opacity": {"value": 1},
          "fill": {"value": "#4c78a8"},
          "ariaRoleDescription": {"value": "point"},
          "description": {
            "signal": "\"date: \" + (timeFormat(datum[\"date\"], '%b %d, %Y')) + \"; price: \" + (format(datum[\"price\"], \"\"))"
          },
          "x": {"scale": "x", "field": "date"},
          "y": {"scale": "y", "field": "price"}
        }
      }
    }
  ],
  "scales": [
    {
      "name": "x",
      "type": "time",
      "domain": {
        "fields": [
          {"data": "source_0", "field": "date"},
          {"data": "data_0", "field": "date"}
        ]
      },
      "range": [0, {"signal": "width"}]
    },
    {
      "name": "y",
      "type": "linear",
      "domain": {
        "fields": [
          {"data": "source_0", "field": "price"},
          [0],
          {"data": "data_0", "field": "price"}
        ]
      },
      "range": [{"signal": "height"}, 0],
      "nice": true,
      "zero": true
    }
  ],
  "axes": [
    {
      "scale": "x",
      "orient": "bottom",
      "gridScale": "y",
      "grid": true,
      "tickCount": {"signal": "ceil(width/40)"},
      "domain": false,
      "labels": false,
      "aria": false,
      "maxExtent": 0,
      "minExtent": 0,
      "ticks": false,
      "zindex": 0
    },
    {
      "scale": "y",
      "orient": "left",
      "gridScale": "x",
      "grid": true,
      "tickCount": {"signal": "ceil(height/40)"},
      "domain": false,
      "labels": false,
      "aria": false,
      "maxExtent": 0,
      "minExtent": 0,
      "ticks": false,
      "zindex": 0
    },
    {
      "scale": "x",
      "orient": "bottom",
      "grid": false,
      "title": "date",
      "labelFlush": true,
      "labelOverlap": true,
      "tickCount": {"signal": "ceil(width/40)"},
      "zindex": 0
    },
    {
      "scale": "y",
      "orient": "left",
      "grid": false,
      "title": "price",
      "labelOverlap": true,
      "tickCount": {"signal": "ceil(height/40)"},
      "zindex": 0
    }
  ]
}