How to customize the color scale in a D3 line chart?

Question

How do I change the color of lines in a d3 line chart, for example in Mike Bostock\'s multi-series D3 line chart.

In his example chart, Mike Bostock uses D3\'s built

Answer 1

for D3 v4

   let color = d3.scaleOrdinal()
      .domain(["New York", "San Francisco", "Austin"])
      .range(["#FF0000", "#009933" , "#0000FF"]);

Answer 2

You're only missing the square brackets around the values in .range() -- it takes an array as argument. So the code should be

var color = d3.scaleOrdinal() // D3 Version 4
  .domain(["New York", "San Francisco", "Austin"])
  .range(["#FF0000", "#009933" , "#0000FF"]);

Complete example here.