addDays(days: number): CustomDate {
   var newDay = this.day + days;
   var newMonth = this.month + Math.floor(newDay / 30);
   newDay = newDay % 30;
   var newYear = this.year + Math.floor(newMonth / 12);
   return new CustomDate(newYear, newMonth, newDay);
 }

 transform(value, args: List<any> = null): any {
   if (isBlank(args) || args.length == 0) {
     throw new BaseException('limitTo pipe requires one argument');
   }
   var limit: int = args[0];
   var left = 0, right = Math.min(limit, value.length);
   if (limit < 0) {
     left = Math.max(0, value.length + limit);
     right = value.length;
   }
   if (isString(value)) {
     return StringWrapper.substring(value, left, right);
   }
   return ListWrapper.slice(value, left, right);
 }

 static calculateStandardDeviation(sample, mean) {
   var deviation = 0;
   ListWrapper.forEach(sample, (x) => { deviation += Math.pow(x - mean, 2); });
   deviation = deviation / (sample.length);
   deviation = Math.sqrt(deviation);
   return deviation;
 }

 static calculateStandardDeviation(samples: number[], mean) {
   var deviation = 0;
   // TODO: use reduce
   samples.forEach(x => deviation += Math.pow(x - mean, 2));
   deviation = deviation / (samples.length);
   deviation = Math.sqrt(deviation);
   return deviation;
 }

 transform(value: any, args: List<any> = null): any {
   if (isBlank(args) || args.length == 0) {
     throw new BaseException('limitTo pipe requires one argument');
   }
   if (!this.supports(value)) {
     throw new InvalidPipeArgumentException(LimitToPipe, value);
   }
   if (isBlank(value)) return value;
   var limit: number = args[0];
   var left = 0, right = Math.min(limit, value.length);
   if (limit < 0) {
     left = Math.max(0, value.length + limit);
     right = value.length;
   }
   if (isString(value)) {
     return StringWrapper.substring(value, left, right);
   }
   return ListWrapper.slice(value, left, right);
 }

 static calculateRegressionSlope(xValues: List<number>, xMean: number, yValues: List<number>,
                                 yMean: number) {
   // See http://en.wikipedia.org/wiki/Simple_linear_regression
   var dividendSum = 0;
   var divisorSum = 0;
   for (var i = 0; i < xValues.length; i++) {
     dividendSum += (xValues[i] - xMean) * (yValues[i] - yMean);
     divisorSum += Math.pow(xValues[i] - xMean, 2);
   }
   return dividendSum / divisorSum;
 }

 this._printStringRow(this._metricNames.map(metricName => {
   var samples = validSamples.map(measureValues => measureValues.values[metricName]);
   var mean = Statistic.calculateMean(samples);
   var cv = Statistic.calculateCoefficientOfVariation(samples, mean);
   var formattedMean = ConsoleReporter._formatNum(mean)
                           // Note: Don't use the unicode character for +- as it might cause
                           // hickups for consoles...
                           return NumberWrapper.isNaN(cv) ?
                           formattedMean :
                           `${formattedMean}+-${Math.floor(cv)}%`;
 }));

 ListWrapper.forEach(sample, (x) => { deviation += Math.pow(x - mean, 2); });

 samples.forEach(x => deviation += Math.pow(x - mean, 2));

  Ancestor} from 'angular2/src/core/annotations/visibility';
import {EventEmitter,
  PropertySetter,
  Attribute} from 'angular2/src/core/annotations/di';
import * as viewModule from 'angular2/src/core/compiler/view';
import {ViewContainer} from 'angular2/src/core/compiler/view_container';
import {NgElement} from 'angular2/src/core/dom/element';
import {Directive,
  onChange,
  onDestroy,
  onAllChangesDone} from 'angular2/src/core/annotations/annotations';
import {BindingPropagationConfig} from 'angular2/change_detection';
import * as pclModule from 'angular2/src/core/compiler/private_component_location';
import {setterFactory} from 'angular2/src/render/dom/view/property_setter_factory';
var _MAX_DIRECTIVE_CONSTRUCTION_COUNTER = 10;
var MAX_DEPTH = Math.pow(2, 30) - 1;
var _undefined = new Object();
var _staticKeys;
class StaticKeys {
  constructor() {
    this.viewId = Key.get(viewModule.View).id;
    this.ngElementId = Key.get(NgElement).id;
    this.viewContainerId = Key.get(ViewContainer).id;
    this.bindingPropagationConfigId = Key.get(BindingPropagationConfig).id;
    this.privateComponentLocationId = Key.get(pclModule.PrivateComponentLocation).id;
  }
  static instance() {
    if (isBlank(_staticKeys))
      _staticKeys = new StaticKeys();
    return _staticKeys;
  }