Continuing trends across Activities and legend labels for multigraphtime

Dear QC experts and others,

Two questions about QC trending (TrendingTask and SliceTrendingTask):

Is it possible to pick up an existing QC trend based on only the path/name of a trend, instead of the Activity that resumeTrend looks at? I would need to trend something where each point comes from different runs, and AFAIK such data has different Activities and the trend will start over.

Second question: is it possible to set custom labels in the legend when trending with multigraphtime?

Thanks a lot!

Best regards,

Hi @mmolande
Regarding resuming the trend, indeed TrendingTask would start a new trend each time there is a new run. However, I do not see a good reason to have it work this way. Thus, I would propose that I change the default behaviour to pick up any latest trend, even from a different activity/run. What do you think?

As for the 2nd question, should I understand you mean labels on the Y axis? Looking at the code, it seems to be doable with graphAxisLabel. Are you asking because it did not work for you?

Hi @pkonopka, your proposal to make it pick up any latest trend sounds good to me! It would also be nice to still be able to reset the trend somehow (i.e. start over with a new trend), in our case I think the time of the resetting would be quite arbitrary, so really a manual way to do it would be nice. (But if not manually, then a time based reset or whatever might also work.)

In the second question I mean that I want to change the texts in the legend when trending many things in the same plot with "TrendingType": "multigraphtime". The documentation says

"multigraphtime": The quantity "Histogram.Var" of all slices is trended as a function of time. All slice-trendings are published on one "TMultiGraph". A legend is provided which contains the numerical boundaries of the slices.

I.e. want to show something else than the numerical boundaries of the slices, if possible.

OK, then agreed with the first one. I think the easiest way to reset the trend would be to temporarily set “resumeTrend” to false for the first run you’d like to have it fresh. I’m not sure what else to propose which would be easier to use.

Regarding the 2nd, I don’t think there is no such feature, but perhaps @mlesch (who wrote it) can prove me wrong.

Hi @mmolande and @pkonopka,

Indeed, in the current version of the SliceTrendingTask, there are no custom labels for the individual slices for the option multigraphtime. I’m not available this week, but I can implement such a feature next week if this is wanted.


Hi @mlesch,

It would indeed be a nice feature to have for us. We will be plotting trends from histograms where the numerical values of the slice ranges don’t mean anything in themselves, but they should be remapped to something understandable.

Thanks a lot!