Function precisionFixed

external/.d3.js:9796–9798

(step)

}

function precisionFixed(step) {
  return Math.max(0, -exponent(Math.abs(step)));
}

function precisionPrefix(step, value) {
  return Math.max(0, Math.max(-8, Math.min(8, Math.floor(exponent(value) / 3))) * 3 - exponent(Math.abs(step)));