@jsmlt/jsmlt/distribution/data/dataset.js

JavaScript Machine Learning

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports["default"] = void 0;

var _datapoint = _interopRequireDefault(require("./datapoint"));

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

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

function _defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } }

function _createClass(Constructor, protoProps, staticProps) { if (protoProps) _defineProperties(Constructor.prototype, protoProps); if (staticProps) _defineProperties(Constructor, staticProps); return Constructor; }

/**
 * Container of data points for a single data set.
 */
var Dataset =
/*#__PURE__*/
function () {
  /**
   * Initialize object properties.
   */
  function Dataset() {
    _classCallCheck(this, Dataset);

    this.numDimensions = 0;
    this.numDatapoints = 0;
    this.datapoints = [];
  }
  /**
   * Add a data point to the data set. Data point should be an array with the number of dimensions
   * used throughout the dataset.
   *
   * @param features Data point features array
   */


  _createClass(Dataset, [{
    key: "addDatapoint",
    value: function addDatapoint(features) {
      // Set the dimensionality of the data if this is the first data point
      if (this.numDatapoints === 0) {
        this.numDimensions = features.length;
      } // Construct data point


      var datapoint = new _datapoint["default"](features); // Check data point validity

      if (!this.isValidDataPoint(datapoint)) {
        throw new Error('Invalid specification of data point.');
      } // Add data point


      this.datapoints.push(datapoint);
      this.numDatapoints += 1;
      return datapoint;
    }
    /**
     * Check whether a data point is valid. A valid data point is an array of the correct number
     * of dimensions.
     *
     * @param datapoint Data point to be checked
     * @return bool Whether the data point is valid
     */

  }, {
    key: "isValidDataPoint",
    value: function isValidDataPoint(datapoint) {
      return Array.isArray(datapoint.features) && datapoint.features.length === this.numDimensions;
    }
    /**
     * Get all data points from this dataset
     *
     * @return Array Data points. Array of datapoint objects
     */

  }, {
    key: "getDataPoints",
    value: function getDataPoints() {
      return this.datapoints;
    }
    /**
     * Get the number of data points in this dataset
     *
     * @return int Number of data points
     */

  }, {
    key: "numDataPoints",
    value: function numDataPoints() {
      return this.datapoints.length;
    }
    /**
     * Get the number of dimensions for the features of data points
     *
     * @return int Dimensionality
     */

  }, {
    key: "getNumDimensions",
    value: function getNumDimensions() {
      return this.numDimensions;
    }
    /**
     * Extract the features from the datapoints and return them in an n x d array, where `n` is the
     * number of data points and `d` is the number of dimensions (number of features per datapoint).
     *
     * @return Array[Array[Number]] Features matrix
     */

  }, {
    key: "getFeaturesArray",
    value: function getFeaturesArray() {
      return this.datapoints.map(function (x) {
        return x.features;
      });
    }
    /**
     * Extract the labels from the datapoints and return them in an array.
     *
     * @return Array[mixed] Labels array
     */

  }, {
    key: "getLabelsArray",
    value: function getLabelsArray() {
      return this.datapoints.map(function (x) {
        return x.classIndex;
      });
    }
  }]);

  return Dataset;
}();

exports["default"] = Dataset;
module.exports = exports.default;