/**
    Calculate the unique values of desired fields
    For example, data like this:
    [{ x: 0, y: -10 }, { x: 10, y: 0 }, { x: 5, y: 10 }]
    and a fields object like this:
    `{'x': d => d.x, 'y': d => d.y}`
    returns an object like this:
    `{ x: [0, 10, 5], y: [-10, 0, 10] }`
    @param {Array<object>} data A flat array of data objects.
    @param {Record<string, Function>} fields An object containing `x`, `y`, `r` or `z` keys that equal an accessor function. If an accessor function returns an array of values, each value will also be evaluated.
    @param {Record<string, boolean>} [sortOptions={}] An object containing `sort`, `x`, `y`, `r` or `z` keys with boolean values that designate how results should be sorted. Default is un-sorted. Pass in `sort: true` to sort all fields or specify fields individually.
    @returns {Record<string, Array<any>>} An object with the same structure as `fields` but instead of an accessor, each key contains an array of unique items.
*/
export default function calcUniques(data: Array<object>, fields: Record<string, Function>, sortOptions?: Record<string, boolean>): Record<string, Array<any>>;