Fix bug when processing files with a single event

[nkx111]

Issue #390.
The bug comes from when finished doing test run(before the actual event processing), REST will push-forward to the next event. Since there is only one event in the file, find the next non-existing event will actually trigger finish reading. Therefore the later processes will get null input event, and cause problems. This fix it to prevent push-forward of event entries during test run, if test run succeeds.

[jgalan]

Nice! I guess some pipelines are failing because it is not the same event that it is being evaluated?

[juanangp]

Nice! I guess some pipelines are failing because it is not the same event that it is being evaluated?

Still don't understand why some pipelines are failing, if you are checking a different event why only one observable has a different value e.g. on the TREX-DM validation pipeline? I would expect several observables failing...

[jgalan]

Nice! I guess some pipelines are failing because it is not the same event that it is being evaluated?

Still don't understand why some pipelines are failing, if you are checking a different event why only one observable has a different value e.g. on the TREX-DM validation pipeline? I would expect several observables failing...

The observable that it is failing is rate_MeanRate_InHz this observable does not only depend on the specific entry being evaluated but it takes the timestamp value of a different event (shifted by 10 events, for example) to calculate the mean value. If there is an extra event ahead this value could be affected. This is a guess.

For the ray-tracing case, all the values are changing, so I guess it is an issue affecting the seed by the fact that there is a different looping scheme? what do you think @nkx111 ?

Merging the following PR should fix axion ray-tracer pipeline rest-for-physics/axionlib#55

[juanangp]

rate_MeanRate_InHz

Then this observable doesn't make much sense to me, in general we should have one observable per event, the rate can be computed later on...

[nkx111]

The observable that it is failing is rate_MeanRate_InHz

I looked into each timestamp of the first 10 events from the pipeline. It changes after this PR. I suspect that it is related somehow with the bug in TRestRawMultiFEMINOSToSignalProcess we already recorded. rest-for-physics/rawlib#36

Before the PR:

$test run: 1582141590.00456

$event 0: 1582141590.00629
$event 1: 1582141590.00456
$event 2: 1582141590.00629
$event 3: 1582141590.00627
$event 4: 1582141590.0068
$event 5: 1582141590.00771
$event 6: 1582141590.00961
...

With this PR:

$test run: 1582141590.00456

$event 0: 1582141590.00456
$event 1: 1582141590.00456
$event 2: 1582141590.00629
$event 3: 1582141590.00627
$event 4: 1582141590.0068
$event 5: 1582141590.00771
$event 6: 1582141590.00961

The assumed "correct behavior", considering the TRestRawMultiFEMINOSToSignalProcess issue, is that the first two events are identical. This is exactly the case with this PR. Before this PR, however, with additional "get-next-event" operation called after test run, event id 0 mysteriously turns into event id 2. The cause of it is unknown to me.

Anyway, despite the first few values of rate_MeanRate_InHz, this observable is correct and meaningful. I think we can just update the checks. In future when we fix the bug in TRestRawMultiFEMINOSToSignalProcess, the validation file shall be updated again. I am not familiar with the FEMINOS daq system, so someone else could help to fix that process?

[nkx111]

For the ray-tracing case, all the values are changing, so I guess it is an issue affecting the seed by the fact that there is a different looping scheme?

Yes, I think this is the case. Previously we are calling TRestAxionGeneratorProcess::ProcessEvent() once more than this PR. So the random value gets changed.

[jgalan]

rate_MeanRate_InHz

Then this observable doesn't make much sense to me, in general we should have one observable per event, the rate can be computed later on...

Yes, that might be a good choice. But does that mean that we need to move TRestEventRateAnalysisProcess to legacy?

[jgalan]

the validation file shall be updated again. I am not familiar with the FEMINOS daq system, so someone else could help to fix that process?

Ok, I think it is clear that it is harmless. I can update the file.

@juanangp Thinking a bit more about, it is interesting to maintain the TRestEventRateAnalysisProcess because it can capture the mean rate at different stages of the processing, while this we cannot do with the final analysis.

For example, in the case that at the raw stage we plug in the TRestEventRateAnalysisProcess it will capture a given mean rate, however, if by some means, the number of events gets reduced when we reach the detector or track domain, then we can plug the TRestEventRateAnalysisProcess there and get a different value. Of course, this process can be also plugged at different raw processing stages where the mean rate is different before or after event discrimination. This is possible using the <cut definition.