Make a clustered bar chart with conditional formatted leged in Deneb.

Hi jaryszek,

You can assign a value to a color encoding by using the field operator in a scale's range after specifying the field to use for its domain, e.g.:

{
  ...
  "encoding": {
    ...
    "color": {
      "field": "MeterCategory",
      "scale": {
        "range": {"field": "Color by Rank"}
      },
      ...
    },
    ...
  },
  ...
}

This is also covered in the Vega-Lite documentation, with an example available here.

Full spec (based on yours above and corrected to work for this case). The visual data set consists of:

• Date (x encoding)
• Sum of CostInBillingCurrency (y encoding)
• MeterCategory (color encoding)
• Color by Rank (color range)

{
  "data": {
    "name": "dataset"
  },
  "mark": {
    "type": "bar",
    "tooltip": true
  },
  "encoding": {
    "x": {
      "field": "Date",
      "type": "temporal",
      "timeUnit": "yearmonthdate",
      "axis": {
        "labelAngle": -40,
        "title": null
      }
    },
    "y": {
      "field": "Sum of CostInBillingCurrency",
      "type": "quantitative",
      "axis": {
        "title": null
      }
    },
    "color": {
      "field": "MeterCategory",
      "scale": {
        "range": {"field": "Color by Rank"}
      },
      "legend": {
        "title": "Rank",
        "labelExpr": "datum.value === 'Others' ? 'Others' : 'Rank ' + datum.value",
        "orient": "right"
      }
    },
    "order": {
      "field": "MeterCategory"
    }
  },
  "config": {
    "view": {
      "stroke": null
    },
    "axisY": {
      "grid": true
    },
    "bar": {
      "size": 10
    }
  }
}

I've also attached a copy of your workbook, along with this working visual.

Thanks for using Deneb!

Daniel