Function copy

docs/source/examples/js/ipyvolume_v0.6.0-dev.1.js:23216–23223

(source, target)

}

function copy(source, target) {
  return target
      .domain(source.domain())
      .range(source.range())
      .interpolate(source.interpolate())
      .clamp(source.clamp())
      .unknown(source.unknown());
}

function transformer() {
  var domain = unit,