vis-utils/lib/extentMulti.js

Utility functions for data visualization

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = extentMulti;

var _extentLimited = require('./extentLimited');

var _extentLimited2 = _interopRequireDefault(_extentLimited);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

/**
 * Compute the extent (min and max) across an array of arrays/objects
 *
 * For example:
 * ```
 * extentMulti([[4, 3], [1, 2]], d => d);
 * > 1, 4
 * ```
 * ```
 * extentMulti([{ results: [{ x: 4 }, { x: 3 }] }, { results: [{ x: 1 }, { x: 2 }] }],
 *   d => d.x, array => array.results);
 * > 1, 4
 * ```
 *
 * @param {Array} outerArray An array of arrays or objects
 * @param {Function} [valueAccessor] How to read a value in the array (defaults to identity)
 * @param {Function} [arrayAccessor] How to read an inner array (defaults to identity)
 * @param {Number} [minPercentile] If provided, limits the min to this percentile value (between 0 and 1).
 *   If provided, the data is sorted by taking the difference of the valueAccessor results.
 * @param {Number} [maxPercentile] If provided, limits the max to this percentile value (between 0 and 1).
 *   If provided, the data is sorted by taking the difference of the valueAccessor results.
 * @return {Array} the extent
 */
function extentMulti(outerArray) {
  var valueAccessor = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : function (d) {
    return d;
  };
  var arrayAccessor = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : function (d) {
    return d;
  };
  var minPercentile = arguments[3];
  var maxPercentile = arguments[4];

  if (!outerArray || !outerArray.length) {
    return undefined;
  }

  // flatten the arrays into one big array
  var combined = outerArray.reduce(function (carry, inner) {
    return carry.concat(arrayAccessor(inner));
  }, []);

  return (0, _extentLimited2.default)(combined, valueAccessor, minPercentile, maxPercentile);
}