vega-lite choropleth with interactively chosen lookup field - Stack Overflow

admin管理员组

文章数量:1122846

I've got a U.S. choropleth with a lookup transform of the counties to the sunrise time (in UTC minutes).

It works, but it's just a single day. My dataset has a column for every day of the calendar year, and I would like to add this dimension to the visualization.

Here is the spec:

  {"encoding": {
    "color": {
      "field": "1-june",
      "type": "quantitative",
      "scale": {"scheme": "rainbow"}
    }
  },
  "transform": [
    {
      "lookup": "id",
      "from": {
        "data": {
          "url": "http://localhost:7777/_fs/resources/data/sunrise-times.csv"
        },
        "key": "geoid",
        "fields": ["1-june"]
      }
    }
  ],
  "mark": "geoshape",
  "width": 650,
  "background": "transparent",
  "$schema": ".json",
  "projection": {"type": "albersUsa"},
  "height": 400,
  "data": {
    "url": "http://localhost:7777/_fs/resources/data/counties-10m.json",
    "format": {"type": "topojson", "feature": "counties"},
    "name": "counties-geojson"
  }
}

Note that in this case I am just showing 1-june, but once again, I want to incorporate the whole calendar year. It seems like I just need to figure out:

• How to encode an array of column names into the spec
• How to interactively choose a column

A slider input could work (a range), if that integer value could be used to index into the column name array.

I tried adding the column name array as an inline dataset, but that didn't seem to be present at runtime. I could make it a parameter as well, but I'm not sure how to reference parameters in an expression.

I'm very open minded as to the best way to implement this.

本文标签： vegalite choropleth with interactively chosen lookup fieldStack Overflow