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Bias Parameter

Dynamically adjust queried values by adding a Param value. The SQL expression is re-computed in the database upon updates.

Loading Example...

Specification

js
import * as vg from "@uwdata/vgplot";

await vg.coordinator().exec([
  vg.loadParquet("walk", "data/random-walk.parquet")
]);

const $point = vg.Param.value(0);

export default vg.vconcat(
  vg.slider({label: "Bias", as: $point, min: 0, max: 1000, step: 1}),
  vg.plot(
    vg.areaY(
      vg.from("walk"),
      {x: "t", y: vg.sql`v + ${$point}`, fill: "steelblue"}
    ),
    vg.width(680),
    vg.height(200)
  )
);
yaml
meta:
  title: Bias Parameter
  description: >
    Dynamically adjust queried values by adding a Param value.
    The SQL expression is re-computed in the database upon updates.
data:
  walk: { file: data/random-walk.parquet }
params:
  point: 0
vconcat:
- input: slider
  label: Bias
  as: $point
  min: 0
  max: 1000
  step: 1
- plot:
  - mark: areaY
    data: { from: walk }
    x: t
    y: { sql: v + $point }
    fill: steelblue
  width: 680
  height: 200
json
{
  "meta": {
    "title": "Bias Parameter",
    "description": "Dynamically adjust queried values by adding a Param value. The SQL expression is re-computed in the database upon updates.\n"
  },
  "data": {
    "walk": {
      "file": "data/random-walk.parquet"
    }
  },
  "params": {
    "point": 0
  },
  "vconcat": [
    {
      "input": "slider",
      "label": "Bias",
      "as": "$point",
      "min": 0,
      "max": 1000,
      "step": 1
    },
    {
      "plot": [
        {
          "mark": "areaY",
          "data": {
            "from": "walk"
          },
          "x": "t",
          "y": {
            "sql": "v + $point"
          },
          "fill": "steelblue"
        }
      ],
      "width": 680,
      "height": 200
    }
  ]
}