Layering Rolling Averages over Raw Values

Plot showing a 30 day rolling average with raw values in the background.

View this example in the online editor

Vega-Lite JSON Specification

{
  "$schema": "https://vega.github.io/schema/vega-lite/v4.json",
  "description": "Plot showing a 30 day rolling average with raw values in the background.",
  "width": 400,
  "height": 300,
  "data": {"url": "data/seattle-weather.csv"},
  "transform": [{
    "window": [
      {
        "field": "temp_max",
        "op": "mean",
        "as": "rolling_mean"
      }
    ],
    "frame": [-15, 15]
  }],
  "encoding": {
    "x": {"field": "date", "type": "temporal", "title": "Date"},
    "y": {"type": "quantitative", "axis": {"title": "Max Temperature and Rolling Mean"}}
  },
  "layer": [
    {
      "mark": {"type": "point", "opacity": 0.3},
      "encoding": {
        "y": {"field": "temp_max", "title": "Max Temperature"}
      }
    },
    {
      "mark": {"type": "line", "color": "red", "size": 3},
      "encoding": {
        "y": {"field": "rolling_mean", "title": "Rolling Mean of Max Temperature"}
      }
    }
  ]
}