Increases or decreases an existing position by the specified factor as of the next bar's open.
broker.AdjustPositionOnOpen( 1.4 )
would increase a position by 40%, while
broker.AdjustPositionOnOpen( .8 )
would decrease the position by 20%.
Increasing a position size will result in adding units since the contract/share additions will have a different entry date than any of the existing units. Decreasing a position size will remove contracts/shares starting with the last unit on, and working back to the first if necessary.
This function is generally used by a Risk Manager Block to lighten a position to meet certain risk restrictions.