README.md

d3-custom-scale

This library allows the user to define custom scales from mathematical functions. The first parameter is the actual transform function, while the second one is the inverse function, used to perform the invert() method.

const asinhScale = scaleCustom(x => Math.asinh(x), x => Math.sinh(x));

scaleCustom() returns a d3 scale, so all scale methods are available

const customScale = scaleCustom(x => x, x => x).domain([0,1]).range([0,100]).clamp(true)

scaleCustom() allows 3 more optional parameters:

• ticks used to customize the ticks displayed
• tickFormat which define how a tick value is converted to string
• nice to provide better control of how the domain is rounded

// full signature
export const scaleCustom: scaleFunction = (
  transform: (x: number) => number,
  untransform: (x: number) => number,
  ticks?: (count: number) => number[],
  tickFormat?: (count?: number, specifier?: string) => (d: number) => string,
  nice?: (count?: number) => ContinuousScale,
) => {}

Installing

npm i d3-custom-scale