Cumulative Sky does not work - intraday

grasshopper ladybug
1

I am doing some analysis where an apparatus tracks the sun.
I used the sun-path component to get me the sun-coordinates so that the normal vector to the tracking geometry keeps looking at the sun.
To go with this - this will be a HONEYBEE RADIATION ANALYSIS - I had created a cumulative sky component - however, for many days, this was giving me results that didn’t add up to some sanity checks.
Finally i realized the root cause today - the cumulative sky component does not work for intraday hourly intervals.

A surest test is - Radiation on Ground (12 to 16 hrs) != Radiation(12-14) + Radiation(14-16)

Also - the minimum interval at which cumulative sky works is 2 hours. I could have made peace with this, but if even that is giving incorrect values, what can be done?
Does anyone have any prior experience here?

A solution then - would be a point-in-time radiation study rather than a cumulative sky radiation study?

Radiation(0-24hrs) gives values which are correct - i could check them with the total solar insolation recieved that day, on online resources.

I cannot directly put the code here, as it has too much stuff related to the problem we trying to solve - if anyone requests, id need to put in a simpler stripped version.

2

The amount of hours from 12-16 and (12-14)+(14-16) is not the same:

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But (12-14)+(15-16) is.
-A.

3

Are you suggesting -
When we doing 12-14 - the analysis is starting at 1200 and stopping at 14:59?
The last hour is included?

If that was the case, then breaking the day into segments like 12-14, 14-16, 16-18 should have resulted in double counting. However, this broken-day analysis is giving me much less radiation than a single 0-24 hr run.

4

I suggest that
12-14 = 12, 13, 14 hours used (3 hours)
14-16 = 14, 15, 16 (3 hours. Hour 14 is double counted)
12-16 = 12, 13, 14, 15, 16 (5 hours)
I didn’t check radiation results. Just mentioning the number of hours used, where one hour happens twice along the whole analysis period. Though it makes sense that starting from 12 will give less radiation than the whole 24 hours … or there is something i’m missing in your explanation? If you mean than just breaking the whole day is giving less than a continuous day, i’lll say that something is wrong in the definition, and you better provide a simple file with the case.
-A.
-A.

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