binarySearch - Cesium Documentation

# binarySearch

#### binarySearch(array, itemToFind, comparator) → Number

  Finds an item in a sorted array.

  Name | Type | Description
  --- | --- | ---
  `array` | Array | The sorted array to search.
  `itemToFind` | Object | The item to find in the array.
  `comparator` | binarySearch~Comparator | The function to use to compare the item to elements in the array.

  ##### Returns:

  The index of `itemToFind` in the array, if it exists. If `itemToFind` does not exist, the return value is a negative number which is the bitwise complement (~) of the index before which the itemToFind should be inserted in order to maintain the sorted order of the array.

  ##### Example:

      // Create a comparator function to search through an array of numbers.
      var comparator = function(a, b) {
          return a - b;
      };
      var numbers = [0, 2, 4, 6, 8];
      var index = Cesium.binarySearch(numbers, 6, comparator); // 3

  Source: Core/binarySearch.js, line 32

### Type Definitions

#### Comparator(a, b) → Number

  A function used to compare two items while performing a binary search.

  Name | Type | Description
  --- | --- | ---
  `a` | Object | An item in the array.
  `b` | Object | The item being searched for.

  ##### Returns:

  Returns a negative value if `a` is less than `b`, a positive value if `a` is greater than `b`, or 0 if `a` is equal to `b`.

  ##### Example:

      function compareNumbers(a, b) {
          return a - b;
      }

  Source: Core/binarySearch.js, line 66