Possible floating point error with skatesum

[bsoule]

Desiderata

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1. Confirm that the bb file still demonstrates the problem
2. TBD

1. A user has a goal with aggday = skatesum.
2. Daily rate of the red line is 0.03 or possibly 0.0299999999999 because floating point.
3. There's a datapoint for Feb 15 that's greater than the daily rate, specifically 0.04583333333333333.
4. It's submitted well before the deadline.
5. When the goal is brained for the deadline, it derails.

It appears that when Beebrain is agging the data and subbing in the daily rate for the actual datapoint value (since actual datapoint value is higher than daily rate), there is some floating point error happening, causing the goal to derail despite that it ought to be safe.

Sample bb file: skatesum_floating_point.bb

(This is arguably a worse-than-baneful bug but it's like a corner case of a corner case. I think.)

Cognata

• Skatesum uses final rate of graph matrix, which is sometimes totally wrong #147
• Skatesum uses rate in rate units instead of daily rate #169

Verbata: floating point hell, baneful bugs, aggday skatesum,