conditionalaxis.vl

{
    "transform": [
        {
            "filter": "datum.symbol === 'GOOG'"
        },
        {
            "filter": {
                "field": "date",
                "timeUnit": "year",
                "range": [
                    2006,
                    2007
                ]
            }
        }
    ],
    "config": {
        "axis": {
            "domainColor": "#ddd",
            "tickColor": "#ddd"
        }
    },
    "mark": "line",
    "data": {
        "url": "https://vega.github.io/vega-lite/data/stocks.csv"
    },
    "width": 400,
    "$schema": "https://vega.github.io/schema/vega-lite/v4.json",
    "encoding": {
        "x": {
            "field": "date",
            "type": "temporal",
            "axis": {
                "tickSize": 30,
                "labelOffset": 4,
                "tickDash": {
                    "value": [
                        2,
                        2
                    ],
                    "condition": {
                        "value": [],
                        "test": {
                            "equal": 1,
                            "field": "value",
                            "timeUnit": "month"
                        }
                    }
                },
                "tickCount": 8,
                "gridDash": {
                    "value": [
                        2,
                        2
                    ],
                    "condition": {
                        "value": [],
                        "test": {
                            "equal": 1,
                            "field": "value",
                            "timeUnit": "month"
                        }
                    }
                },
                "labelExpr": "[timeFormat(datum.value, '%b'), timeFormat(datum.value, '%m') == '01' ? timeFormat(datum.value, '%Y') : '']",
                "labelPadding": -24,
                "labelAlign": "left"
            }
        },
        "y": {
            "field": "price",
            "type": "quantitative"
        }
    },
    "description": "Line chart with conditional axis ticks, labels, and grid."
}