{
  "$schema": "https://vega.github.io/schema/vega/v5.json",
  "background": "white",
  "padding": 5,
  "width": 300,
  "height": 100,
  "style": "cell",
  "data": [
    {
      "name": "source_0",
      "url": "data/stocks.csv",
      "format": {"type": "csv", "parse": {"date": "date"}},
      "transform": [
        {"type": "filter", "expr": "datum.symbol !== 'GOOG'"},
        {
          "field": "date",
          "type": "timeunit",
          "units": ["year", "month", "date"],
          "as": ["yearmonthdate_date", "yearmonthdate_date_end"]
        },
        {
          "type": "aggregate",
          "groupby": ["yearmonthdate_date", "symbol"],
          "ops": ["sum"],
          "fields": ["price"],
          "as": ["sum_price"]
        },
        {
          "type": "filter",
          "expr": "isValid(datum[\"sum_price\"]) && isFinite(+datum[\"sum_price\"])"
        }
      ]
    }
  ],
  "marks": [
    {
      "name": "marks",
      "type": "rect",
      "style": ["rect"],
      "from": {"data": "source_0"},
      "encode": {
        "update": {
          "fill": {"scale": "color", "field": "sum_price"},
          "description": {
            "signal": "\"Time: \" + (timeFormat(datum[\"yearmonthdate_date\"], '%Y')) + \"; symbol: \" + (isValid(datum[\"symbol\"]) ? datum[\"symbol\"] : \"\"+datum[\"symbol\"]) + \"; Price: \" + (format(datum[\"sum_price\"], \"\"))"
          },
          "x": {"scale": "x", "field": "yearmonthdate_date"},
          "width": {"scale": "x", "band": 1},
          "y": {"scale": "y", "field": "symbol"},
          "height": {"scale": "y", "band": 1}
        }
      }
    }
  ],
  "scales": [
    {
      "name": "x",
      "type": "band",
      "domain": {
        "data": "source_0",
        "field": "yearmonthdate_date",
        "sort": true
      },
      "range": [0, {"signal": "width"}],
      "paddingInner": 0,
      "paddingOuter": 0
    },
    {
      "name": "y",
      "type": "band",
      "domain": {"data": "source_0", "field": "symbol", "sort": true},
      "range": [0, {"signal": "height"}],
      "paddingInner": 0,
      "paddingOuter": 0
    },
    {
      "name": "color",
      "type": "linear",
      "domain": {"data": "source_0", "field": "sum_price"},
      "range": "heatmap",
      "interpolate": "hcl",
      "zero": false
    }
  ],
  "axes": [
    {
      "scale": "x",
      "orient": "bottom",
      "grid": false,
      "title": "Time",
      "format": "%Y",
      "labelAngle": 0,
      "labelOverlap": false,
      "formatType": "time",
      "labelBaseline": "top",
      "encode": {
        "labels": {
          "update": {
            "fill": [
              {
                "test": "time(datetime(2012, month(datum[\"value\"]), date(datum[\"value\"]), 0, 0, 0, 0))===time(datetime(2012, 0, 1, 0, 0, 0, 0))",
                "value": "black"
              },
              {"value": null}
            ]
          }
        },
        "ticks": {
          "update": {
            "stroke": [
              {
                "test": "time(datetime(2012, month(datum[\"value\"]), date(datum[\"value\"]), 0, 0, 0, 0))===time(datetime(2012, 0, 1, 0, 0, 0, 0))",
                "value": "black"
              },
              {"value": null}
            ]
          }
        }
      },
      "zindex": 1
    },
    {"scale": "y", "orient": "left", "grid": false, "zindex": 1}
  ],
  "legends": [
    {
      "title": "Price",
      "fill": "color",
      "gradientLength": {"signal": "clamp(height, 64, 200)"}
    }
  ]
}