While trying to track down a bug in my code, I noticed that the QC indicator values sometimes are quite a bit off from my other sources. I know that QC filter price data in their own way, so the price can be a little different. But what I noticed when comparing to TradingView, was that the price matched, but the indicators gave different values. For instance, NVDA (NVIDIA) on 2021-01-05:
- QC Price: 524.54
- TW Price: 524.54
- QC RateOfChangePercent(100): 14.67
- TW RateOfChangePercent(100): 17.24

EMA20 and EMA50 are also a bit off, but not as much.

ROC and EMA are simple calculations, so I don't understand why the results are different when the price data seems to be the same. I have double checked TradingViews indicator values using Pine Script, and they seem to be correct. TradingView is using bars (and not time periods) when calculating indicator values. I don't know if this is different in QC.

Any explanation?
 

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