{
    "transform": [
        {
            "window": [
                {
                    "op": "count",
                    "as": "index"
                }
            ]
        },
        {
            "fold": [
                "petalLength",
                "petalWidth",
                "sepalLength",
                "sepalWidth"
            ]
        },
        {
            "groupby": [
                "key"
            ],
            "joinaggregate": [
                {
                    "op": "min",
                    "as": "min",
                    "field": "value"
                },
                {
                    "op": "max",
                    "as": "max",
                    "field": "value"
                }
            ]
        },
        {
            "as": "normVal",
            "calculate": "(datum.value - datum.min) / (datum.max-datum.min)"
        },
        {
            "as": "mid",
            "calculate": "(datum.min + datum.max) / 2"
        }
    ],
    "height": 300,
    "config": {
        "style": {
            "tick": {
                "orient": "horizontal",
                "tooltip": null
            },
            "label": {
                "dx": -5,
                "tooltip": null,
                "align": "right",
                "baseline": "middle"
            }
        },
        "view": {
            "stroke": null
        },
        "axisX": {
            "labelAngle": 0,
            "domain": false,
            "tickColor": "#ccc"
        }
    },
    "data": {
        "url": "https://vega.github.io/vega-lite/data/iris.json"
    },
    "width": 600,
    "$schema": "https://vega.github.io/schema/vega-lite/v4.json",
    "layer": [
        {
            "mark": {
                "opacity": 0.3,
                "type": "line"
            },
            "encoding": {
                "color": {
                    "field": "species",
                    "type": "nominal"
                },
                "tooltip": [
                    {
                        "field": "petalLength",
                        "type": "quantitative"
                    },
                    {
                        "field": "petalWidth",
                        "type": "quantitative"
                    },
                    {
                        "field": "sepalLength",
                        "type": "quantitative"
                    },
                    {
                        "field": "sepalWidth",
                        "type": "quantitative"
                    }
                ],
                "x": {
                    "field": "key",
                    "type": "nominal"
                },
                "detail": {
                    "field": "index",
                    "type": "nominal"
                },
                "y": {
                    "field": "normVal",
                    "type": "quantitative",
                    "axis": null
                }
            }
        },
        {
            "mark": {
                "color": "#ccc",
                "type": "rule"
            },
            "encoding": {
                "x": {
                    "field": "key",
                    "type": "nominal",
                    "axis": {
                        "title": null
                    }
                },
                "detail": {
                    "aggregate": "count",
                    "type": "quantitative"
                }
            }
        },
        {
            "mark": {
                "style": "label",
                "type": "text"
            },
            "encoding": {
                "text": {
                    "field": "max",
                    "aggregate": "max",
                    "type": "quantitative"
                },
                "x": {
                    "field": "key",
                    "type": "nominal"
                },
                "y": {
                    "value": 0
                }
            }
        },
        {
            "mark": {
                "style": "label",
                "type": "text"
            },
            "encoding": {
                "text": {
                    "field": "mid",
                    "aggregate": "min",
                    "type": "quantitative"
                },
                "x": {
                    "field": "key",
                    "type": "nominal"
                },
                "y": {
                    "value": 150
                }
            }
        },
        {
            "mark": {
                "style": "label",
                "type": "text"
            },
            "encoding": {
                "text": {
                    "field": "min",
                    "aggregate": "min",
                    "type": "quantitative"
                },
                "x": {
                    "field": "key",
                    "type": "nominal"
                },
                "y": {
                    "value": "height"
                }
            }
        }
    ],
    "description": "Parallel coordinates plot with manual generation of parallel axes"
}