Created
April 30, 2022 18:59
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Time alignment problem
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| from collections import defaultdict | |
| def get_time_offsets(events): | |
| '''events: list of time pairs (dev1, t1, dev2, t2) such that event at t1 guaranteed happens before event at t2 | |
| Return dict of dev:(offset, error) | |
| then, adding offset to timestamps from its dev translates them into a common timespace. | |
| ''' | |
| devs = defaultdict(lambda: ([], [])) # [dev] -> (events with dev time before, events with dev time after) | |
| for e in events: | |
| dev1, t1, dev2, t2 = e | |
| devs[dev1][0].append(e) | |
| devs[dev2][1].append(e) | |
| highs = defaultdict(dict) | |
| lows = defaultdict(dict) | |
| for dev1, t1, dev2, t2 in events: | |
| highs[dev1][dev2] = min(t2-t1, highs[dev1][dev2]) | |
| lows[dev2][dev1] = max(t1-t2, lows[dev2][dev1]) | |
| print(highs) | |
| print(lows) | |
| return {} | |
| A,B,C='ABC' | |
| # timeline: | |
| # A 17 | |
| # B 18 20 22 | |
| # C 30 | |
| events = [ | |
| (B, 18, C, 30), # B+18 < C+30 | |
| (C, 30, B, 20), # C+30 < B+20 | |
| (B, 20, A, 17), # B+20 < A+17 | |
| (A, 17, B, 22), # A+17 < B+22 | |
| ] | |
| #C+10 < B < C+12 | |
| # B < A-3 | |
| #A < B+5 | |
| golden_offsets = [{ | |
| A: (4, 1), | |
| B: (0, 0), | |
| C: (-11, 1) | |
| }, { | |
| A: (0, 1), | |
| B: (-4, 0), | |
| C: (-15, 1) | |
| }, { | |
| A: (15, 1), | |
| B: (11, 0), | |
| C: (0, 1) | |
| }] | |
| assert get_time_offsets(events) in golden_offsets |
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