There is a mini stalactite developing slightly at x=58-59, quite deep now.
I am not sure about that, maybe random variation?
I powered the modems down for several hours overnight because of a lightning scare. When they came back up the notch - supposed incipient hollow curve was still exactly the same. By the chosen geometric definition of hollow curve, it definitely qualifies, but I’m not sure it qualifies as a
disease that develops; could be a permanent quirk or permanent disease though. We will have to see if it does grow.
I added an additional parameter ‘chord2 notch min height’ set to 1.5 dB. This is subtracted from the drop height below the midpoint as in
bool hollow_curve2 = y5 < ymid2 - chord2_notch_min_height;This means that small notches are ignored when the parameter’s value is set large enough and the definition of ‘notch’ is that detected by chord2, that is the chord x=40 to x=60.
This worked perfectly, blocking the detection of small chord2 notches if they are regarded as not genuine ‘disease’, although this classification is questionable. I would say that notches are only bogus if they do not go on to develop into something larger.
After a resynch on Tue afternoon, it seems the chord2 notch phenomenon has gone away. Who knows how long for though. At least the flexible twin-chord test and the filter ‘chord2 notch min height’ parameter are available as a future flexible guard.
Current line 4, Tue afternoon after the notch went away:
39 39.2500
40 40.0625
41 40.6250
42 40.8125
43 41.0625
44 41.2500
45 41.5000
46 35.3125
47 41.1875
48 41.5625
49 41.5000
50 38.6250
51 41.6250
52 41.1250
53 41.4375
54 41.3125
55 41.0000
56 40.8750
57 40.8125
58 39.0625
59 39.0000
60 39.9375
61 40.0000
62 40.2500
63 40.0625
64 39.4375
65 39.5000
66 39.0625