Update on New Bar or Every Tick???

 

Hi

I hope I can explain my question properly ...

Most of the examples I see take no account of whether a price is the first price of a new bar and seem to calculate all of the values for custom indicators on every new tick. Is this necessary? I would have thought that you could calculate the values for your custom indicator on the very first tick and then update the array only on the start of a new bar ? If that is the case can I simply shift the array and then just update the current value or do I need to calculate the whole array again ...

Hope that is sort of a clear question!

Thanks

Paul