{
  "$schema": "https://vega.github.io/schema/vega/v5.json",
  "description": "A bubble plot showing the correlation between health and income for 187 countries in the world (modified from an example in Lisa Charlotte Rost's blog post 'One Chart, Twelve Charting Libraries' --http://lisacharlotterost.github.io/2016/05/17/one-chart-code/).",
  "background": "white",
  "padding": 5,
  "width": 500,
  "height": 300,
  "style": "cell",
  "data": [
    {"name": "view_store"},
    {
      "name": "source_0",
      "url": "https://raw.githubusercontent.com/vega/vega-datasets/master/data/gapminder-health-income.csv",
      "format": {"type": "csv", "delimiter": ","},
      "transform": [
        {
          "type": "filter",
          "expr": "isValid(datum[\"health\"]) && isFinite(+datum[\"health\"]) && isValid(datum[\"income\"]) && isFinite(+datum[\"income\"]) && isValid(datum[\"population\"]) && isFinite(+datum[\"population\"])"
        }
      ]
    }
  ],
  "signals": [
    {
      "name": "unit",
      "value": {},
      "on": [
        {"events": "mousemove", "update": "isTuple(group()) ? group() : unit"}
      ]
    },
    {"name": "view", "update": "vlSelectionResolve(\"view_store\", \"union\")"},
    {
      "name": "view_income",
      "on": [
        {"events": [{"source": "view", "type": "dblclick"}], "update": "null"},
        {
          "events": {"signal": "view_translate_delta"},
          "update": "panLog(view_translate_anchor.extent_x, -view_translate_delta.x / width)"
        },
        {
          "events": {"signal": "view_zoom_delta"},
          "update": "zoomLog(domain(\"x\"), view_zoom_anchor.x, view_zoom_delta)"
        }
      ]
    },
    {
      "name": "view_health",
      "on": [
        {"events": [{"source": "view", "type": "dblclick"}], "update": "null"},
        {
          "events": {"signal": "view_translate_delta"},
          "update": "panLinear(view_translate_anchor.extent_y, view_translate_delta.y / height)"
        },
        {
          "events": {"signal": "view_zoom_delta"},
          "update": "zoomLinear(domain(\"y\"), view_zoom_anchor.y, view_zoom_delta)"
        }
      ]
    },
    {
      "name": "view_tuple",
      "on": [
        {
          "events": [{"signal": "view_income || view_health"}],
          "update": "view_income && view_health ? {unit: \"\", fields: view_tuple_fields, values: [view_income,view_health]} : null"
        }
      ]
    },
    {
      "name": "view_tuple_fields",
      "value": [
        {"field": "income", "channel": "x", "type": "R"},
        {"field": "health", "channel": "y", "type": "R"}
      ]
    },
    {
      "name": "view_translate_anchor",
      "value": {},
      "on": [
        {
          "events": [{"source": "scope", "type": "mousedown"}],
          "update": "{x: x(unit), y: y(unit), extent_x: domain(\"x\"), extent_y: domain(\"y\")}"
        }
      ]
    },
    {
      "name": "view_translate_delta",
      "value": {},
      "on": [
        {
          "events": [
            {
              "source": "window",
              "type": "mousemove",
              "consume": true,
              "between": [
                {"source": "scope", "type": "mousedown"},
                {"source": "window", "type": "mouseup"}
              ]
            }
          ],
          "update": "{x: view_translate_anchor.x - x(unit), y: view_translate_anchor.y - y(unit)}"
        }
      ]
    },
    {
      "name": "view_zoom_anchor",
      "on": [
        {
          "events": [{"source": "scope", "type": "wheel", "consume": true}],
          "update": "{x: invert(\"x\", x(unit)), y: invert(\"y\", y(unit))}"
        }
      ]
    },
    {
      "name": "view_zoom_delta",
      "on": [
        {
          "events": [{"source": "scope", "type": "wheel", "consume": true}],
          "force": true,
          "update": "pow(1.001, event.deltaY * pow(16, event.deltaMode))"
        }
      ]
    },
    {
      "name": "view_modify",
      "on": [
        {
          "events": {"signal": "view_tuple"},
          "update": "modify(\"view_store\", view_tuple, true)"
        }
      ]
    }
  ],
  "marks": [
    {
      "name": "marks",
      "type": "symbol",
      "clip": true,
      "style": ["circle"],
      "interactive": true,
      "from": {"data": "source_0"},
      "encode": {
        "update": {
          "opacity": {"value": 0.7},
          "fill": {"value": "#000"},
          "ariaRoleDescription": {"value": "circle"},
          "description": {
            "signal": "\"health: \" + (format(datum[\"health\"], \"\")) + \"; income: \" + (format(datum[\"income\"], \"\")) + \"; population: \" + (format(datum[\"population\"], \"\"))"
          },
          "x": {"scale": "x", "field": "income"},
          "y": [
            {
              "test": "!isValid(datum[\"health\"]) || !isFinite(+datum[\"health\"])",
              "field": {"group": "height"}
            },
            {"scale": "y", "field": "health"}
          ],
          "size": {"scale": "size", "field": "population"},
          "shape": {"value": "circle"}
        }
      }
    }
  ],
  "scales": [
    {
      "name": "x",
      "type": "log",
      "domain": {"data": "source_0", "field": "income"},
      "domainRaw": {"signal": "view[\"income\"]"},
      "range": [0, {"signal": "width"}],
      "nice": true
    },
    {
      "name": "y",
      "type": "linear",
      "domain": {"data": "source_0", "field": "health"},
      "domainRaw": {"signal": "view[\"health\"]"},
      "range": [{"signal": "height"}, 0],
      "zero": false,
      "nice": true
    },
    {
      "name": "size",
      "type": "linear",
      "domain": {"data": "source_0", "field": "population"},
      "range": [0, 361],
      "zero": true
    }
  ],
  "axes": [
    {
      "scale": "x",
      "orient": "bottom",
      "gridScale": "y",
      "grid": true,
      "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": "income",
      "labelFlush": true,
      "labelOverlap": "greedy",
      "zindex": 0
    },
    {
      "scale": "y",
      "orient": "left",
      "grid": false,
      "title": "health",
      "minExtent": 30,
      "labelOverlap": true,
      "tickCount": {"signal": "ceil(height/40)"},
      "zindex": 0
    }
  ],
  "legends": [
    {
      "size": "size",
      "symbolType": "circle",
      "title": "population",
      "encode": {
        "symbols": {
          "update": {
            "fill": {"value": "#000"},
            "opacity": {"value": 0.7},
            "stroke": {"value": "transparent"}
          }
        }
      }
    }
  ]
}