Deneb chart with dynamic x-axis

Hi vivians ,

Not sure if it works.

{
  "data": {
    "name": "dataset"
  },
  "transform": [
    {
      "joinaggregate": [
        {"op": "max", "field": "End of Month", "as": "max"},
        {"op": "min", "field": "Start of Month", "as": "min"}
      ]
    },
    {"calculate": "datum.max", "as": "max"},
    {"calculate": "datum.min", "as": "min"},
    
    // Now separately aggregate for size without affecting joinaggregate
    {
      "aggregate": [
        {"op": "sum", "field": "Point", "as": "sum_Point"}
      ],
      "groupby": ["Country", "Date"]  // Group by the required fields to avoid affecting X-axis
    }
  ],
  "params": [
    {"name": "max", "expr": "data('data_0')[0]['max']"},
    {"name": "min", "expr": "data('data_0')[0]['min']}
  ],  
  "mark": {
    "type": "circle"
  },
  "encoding": {
    "x": {
      "field": "Date", 
      "timeUnit": "yearmonthdate",
      "type": "temporal",
      "scale": {"domain": {"expr": "[min,max]"}},
      "axis": {
        "tickCount": 10,
        "labelAlign": "left",
        "labelExpr": "[timeFormat(datum.value, '%b'), timeFormat(datum.value, '%m') == '01' ? timeFormat(datum.value, '%Y') : '']",
        "labelOffset": 4,
        "labelPadding": -24,
        "tickSize": 30,
        "gridDash": {
          "condition": {"test": {"field": "value", "timeUnit": "month", "equal": 1}, "value": []},
          "value": [2, 2]
        },
        "tickDash": {
          "condition": {"test": {"field": "value", "timeUnit": "month", "equal": 1}, "value": []},
          "value": [2, 2]
        }
      }
    },
    "y": {
      "field": "Country",
      "type": "nominal"
    },
    "size": {
      "field": "sum_Point",  // Use the aggregated sum of Points for size
      "type": "quantitative",
      "legend": null
    },
    "color": {
      "field": "Type",
      "legend": null
    }
  }
}

If the problem persists, please consider posting it on the vega forum.

Best Regards,

Wearsky