How to start bar from 1 instead of 0 in Vega Lite?

I'm plotting the diff time series [1.1, 0.9, 1.2, ...].

And as the values are relative multipliers, the middle is 1 and not 0.

Is there a way to tell Vega Lite to start bar with 1?

So for the value 1.1 the bar will be start: 1, end: 1.1 and for 0.9 it will be start: 1, end: 0.9?

Solution

You can use a y2 encoding with datum set to 1. For example (vega editor):

{
  "data": {
    "values": [
      {"x": "A", "y": 0.9},
      {"x": "B", "y": 0.8},
      {"x": "C", "y": 1.1},
      {"x": "D", "y": 1.2},
      {"x": "E", "y": 0.9},
      {"x": "F", "y": 1.3}
    ]
  },
  "mark": "bar",
  "encoding": {
    "x": {"type": "nominal", "field": "x"},
    "y": {
      "type": "quantitative",
      "field": "y",
      "scale": {"domain": [0.6, 1.4]}
    },
    "y2": {"datum": 1}
  }
}