Vegas (Scala/Spark/Vega) 为每个数据点着色

Question

Vegas("A scatterplot").
  withDataFrame(neuronnet_activation_df).
  mark(Point).
  encodeX("s", Quantitative).
  encodeY("d", Quantitative).
  encodeColor(field="feature_0_prediction",scale=Scale(rangeNominals=List("#c41f01", "#00c610"))).
  show

是否可以用特定的 RGB 或 aRGB 值绘制每个点？我已经计算了颜色，所以我不需要使用范围，而且我的数据的颜色范围不是线性的。

Answer 1

我不确定这如何映射到 Vegas 语法，但在 Vega-Lite 中，您可以通过将颜色代码作为数据传递并将色标设置为 null 来实现。例如：

{
  "data": {
    "values": [
      {"s": 1, "d": 1, "color": "#c41f01"},
      {"s": 3, "d": 3, "color": "#00c610"}
    ]
  },
  "mark": {"type": "circle", "size": 200},
  "encoding": {
    "color": {"type": "nominal", "field": "color", "scale": null},
    "x": {"type": "quantitative", "field": "s"},
    "y": {"type": "quantitative", "field": "d"}
  },
  "$schema": "https://vega.github.io/schema/vega-lite/v2.6.0.json"
}

Vegas (Scala/Spark/Vega) 为每个数据点着色

Vegas (Scala/Spark/Vega) color every data point

scala

apache-spark

vega

vega-lite

vegas-viz