code: function _upHandler(e) {
        if (_settings('mouseEnabled') && _isMouseDown) {
          _isMouseDown = false;
          if (_movingTimeoutId)
            clearTimeout(_movingTimeoutId);
  
          _camera.isMoving = false;
  
          var x = sigma.utils.getX(e),
              y = sigma.utils.getY(e);
  
          if (_isMoving) {
            sigma.misc.animation.killAll(_camera);
            sigma.misc.animation.camera(
              _camera,
              {
                x: _camera.x +
                  _settings('mouseInertiaRatio') * (_camera.x - _lastCameraX),
                y: _camera.y +
                  _settings('mouseInertiaRatio') * (_camera.y - _lastCameraY)
              },
              {
                easing: 'quadraticOut',
                duration: _settings('mouseInertiaDuration')
              }
            );
          } else if (
            _startMouseX !== x ||
            _startMouseY !== y
          )
            _camera.goTo({
              x: _camera.x,
              y: _camera.y
            });
  
          _self.dispatchEvent('mouseup',
            sigma.utils.mouseCoords(e));
  
          // Update _isMoving flag:
          _isMoving = false;
        }
      }
docs: The handler listening to the 'up' mouse event. It will stop dragging the
  graph.
  
  @param {event} e A mouse event.