[d2n-analysis-talk] BB TDC cuts

[Brad Sawatzky]

On Wed, 26 May 2010, MATTHEW R POSIK wrote:

> I just checked the TDC hits and it seems like most of the (15 of the
> TDCs) are arrays of 16 and of the other  TDCs with array length less
> than 16, only one was less than the 6 hits that I was looping over
> (For the H2 elastic runs). So I just fixed that. On the TDCs with
> array length 16, there seems to be events in hits 1-6 and then a large
> gap until hit 16 where there is what looks to be one event.

That doesn't make sense to me.  All of the DL class variables have
a hardcoded hit array with 16 elements (see MxHits in THaDecData.C).
The 1877s have a hit buffer depth that is typically programmed to be 6.

If NData.DL.foo == X, then the data elements
    DL.foo[0] .. DL.foo[X-1] are meaninful data
    DL.foo[-1]               is god knows what (indexing out of bounds)
    DL.foo[X] .. DL.foo[15]  is god knows what (old data or whatever was
                                in memory when the array was
                                instantiated)
    DL.foo[16]               is god knows what (indexing out of bounds,
                                possibly the first hit in the array
                                allocated for the next DecData variable.
                                Who knows...)

You say there are DecData hit arrays that have a length other than 16?
Are those associated with the DecData VDC or TrigBit stuff?

-- Brad

-- 
Brad Sawatzky, PhD <brads at jlab.org>  -<>-  Jefferson Lab / Hall C / C111
Ph: 757-269-5947  -<>-  Fax: 757-269-5235  -<>- Pager: brads-page at jlab.org
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