0👍
I’ve solved like this. Just change the condition on context depending your task.
const test = (ctx, value) => (ctx.p1DataIndex >= showLast ? value : undefined)
const point = (ctx, trainCol, testCol) => ctx.index >= showLast ? testCol : trainCol
const data = {
labels: trainDates.map(val => val.format("DD-MM")),
datasets: [
{
label: "Test plot",
data: values,
borderColor: "rgb(75, 192, 192)",
fill: false,
pointStyle: "circle",
pointBackgroundColor: ctx => point(ctx, "rgb(75, 192, 192)", "rgb(192,75,75)"),
pointBorderColor: ctx => point(ctx, "rgb(75, 192, 192)", "rgb(192,75,75)"),
segment: {
borderColor: ctx => test(ctx, "rgb(192,75,75)"),
},
},
],}
Source:stackexchange.com