PLOT_DRAW_BEGIN vs filling start of buffer with empty values

[Jean Sebastien Paquet]

If you don't want to waste cpu when you don't need to calculate indicator values for all available rates, is it best to fill all values you want to skip with empty values or is it better to just use PLOT_DRAW_BEGIN to set where you want to start and make your calculation cycle start on that index instead of index 0?

I've tried both methods but I wonder which one is recommended for better performance. It seems like one method would prioritize speed and the other would use up less memory space, I'm not sure though...

[William Roeder]

Jeepack: PLOT_DRAW_BEGIN to set where you want to start and make your calculation cycle start on that index instead of index 0?

I've tried both methods but I wonder which one is recommended for better performance. It seems like one method would prioritize speed and the other would use up less memory space,

1. Never worry about performance, until you have a problem and have measured it, isolated where, changed it, and re-verified. I doubt there is any measurable difference.

2. Unless you don't look at any previous bars (zero lookback), you must “start on that index” to avoid array exceeded.
             How to do your lookbacks correctly #9 — #14 & #19 (2016)

3. I've never used draw begin on MT4, just let the buffer values default to empty. On MT5, most indicators just initialize the buffer to empty when previous_calculated is zero.
   

[Jean Sebastien Paquet]

That helps a lot, thanks for the tips.