Question: What is the purpose for having both price0Cumulative and price1Cumulative? about v2-core HOT 5 CLOSED

Basically

sum(a/b + c/d + ef) != inv(sum(b/a + d/c +f/e))

When using the oracle, you need one of the accumulators to get a price for token0 and the other to get a price for token1. Will invite you to the oracle example although its not in any finalized state.

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Hmm, this doesn't make sense to me because for any given price (regardless how you got that price) you should be able to take the inverse to get the price the other direction. This means if a price is the output of some moving average formula (doesn't matter which one), then you should be able to take the inverse of that to get the other price.

Happen to have any examples or pro-tips that will help me grok why this is not true?

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@MicahZoltu it's because a price is a ratio of two values with different units. here's a somewhat helpful series of explanations: https://math.stackexchange.com/questions/3107661/why-is-the-inverse-of-an-average-of-numbers-not-the-same-as-the-average-of-the-i

and if you want to look at numbers, here's the most dumbed-down example: https://docs.google.com/spreadsheets/d/1wMzZabuGYknwWvX9pAR4s1yiNyfQ3DDE-c0Vb9xLxuk/edit?usp=sharing

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This does not make my brain happy. It very much dislikes it when intuition disagrees with reality.

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We'll add some clarifications in the comments. Closing in favor of #45

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