SAMS-locality-choropleth.json

{
  "$schema": "https://vega.github.io/schema/vega-lite/v3.json",
  "description": "Basic choropleth (rate/ratio)",
  "autosize": "fit",
  "width": 600,
  "height": 300,
  "title": "Number of SAMS packages, 2018/19",
  "data": {
    "url": "https://www.trafforddatalab.io/spatial_data/council_defined/trafford_localities.geojson",
    "format": {"property": "features"}
  },
  "transform": [
    {
      "lookup": "properties.locality",
      "from": {
        "data": {
          "values": [
            {"locality": "Central", "value": 286},
            {"locality": "North", "value": 232},
            {"locality": "South", "value": 326},
            {"locality": "West", "value": 218}
          ]
        },
        "key": "locality",
        "fields": ["value"]
      }
    }
  ],
  "mark": {"type": "geoshape", "stroke": "white", "strokeWidth": 1},
  "projection": {"type": "mercator"},
  "encoding": {
    "color": {
      "field": "value",
      "scale": {"scheme": "blues"},
      "type": "quantitative",
      "legend": {
        "title": null,
        "direction": "horizontal",
        "orient": "bottom-left"
      }
    },
        "tooltip": [
          {"field": "properties.locality", "type": "nominal", "title": "Locality"},
          {
            "field": "value",
            "type": "quantitative",
            "title": "Rate"
          }
        ]
  },
  "config": {"view": {"stroke": "transparent"}}
}