NinjaScript > Language Reference > Common > OnBarUpdate()

Definition

Determines how often OnBarUpdate() is called for each bar. OnBarClose means once at the close of the bar. OnEachTick means on every single tick. OnPriceChange means once for each price change. If there were two ticks in a row with the same price, the second tick would not trigger OnBarUpdate(). This can improve performance if calculations are only needed when new values are possible.

Notes:

1.On a historical data set, only the OHLCVT of the bar is known and not each tick that made up the bar. As a result, State.Historical data processes OnBarUpdate() only on the close of each historical bar even if this property is set to OnEachTick or OnPriceChange. You can use TickReplay or a Multi-time frame script to obtain intrabar data.

2.When set to Calculate OnPriceChange, the OnBarUpdate() method is ONLY called when the price has changed which does not necessarily occur the end of the close of the bar

Property Value

An enum value determining the how frequently OnBarUpdate() will be called. Default value is set to Calculate.OnBarClose

Warning: If your script relies on volume updates OnPriceChange should NOT be used since it can potentially miss volume updates if they occur at the same price

Syntax

Calculate.OnBarClose

Calculate.OnEachTick

Calculate.OnPriceChange

Tips

1.Calculating indicators or systems for each incoming tick can be CPU intensive. Only calculate indicators on each incoming tick if you have a requirement to calculate it intra-bar.

2.For an example of how to separate some logic to be Calculate = Calculate.OnBarClose and other logic to be .OnEachTick please see this reference sample.

3.Embedded scripts within a calling parent script should not use a different Calculate property since it is already utilizing the Calculate property of the parent script (i.e. the strategy your indicator is called from).

4. Typically this property would be set in State.SetDefaults, however scripts that require Calculate to be set by the developer must set this property in State.Historical in its OnStateChange() in order to ensure that if this script is a child (hosted) that the parent.Calculate property which is adopted by the child is overridden again.

Examples


protected override void OnStateChange() { if (State == State.SetDefaults) { // Calculate on the close of each bar Calculate = Calculate.OnBarClose; } }