diff options
| -rw-r--r-- | lib/postrunner/DailySleepAnalyzer.rb | 28 |
1 files changed, 19 insertions, 9 deletions
diff --git a/lib/postrunner/DailySleepAnalyzer.rb b/lib/postrunner/DailySleepAnalyzer.rb index 05875e3..856c6b1 100644 --- a/lib/postrunner/DailySleepAnalyzer.rb +++ b/lib/postrunner/DailySleepAnalyzer.rb @@ -277,7 +277,13 @@ module PostRunner # During the nightly sleep the heart rate is alternating between a high # and a low frequency. The actual frequencies vary so that we need to look - # for the transitions to classify each sample as high or low. + # for the transitions to classify each sample as high or low. Research has + # shown that sleep cycles are roughly 90 minutes long. The early cycles + # have a lot more deep sleep (low HR) and less REM (high HR) while with + # every cycle the deep sleep phase shortens and the REM phase gets longer. + # We assume that a normalized half-phase is at least 25 minutes long and + # the weight shifts by 4 minutes towards the high HR (REM) phase with + # every phase. def categorize_sleep_heart_rate @sleep_heart_rate_classification = Array.new(TIME_WINDOW_MINUTES, nil) @@ -301,10 +307,12 @@ module PostRunner if current_category == :high_hr if last_heart_rate > @heart_rate[i] # High/low transition found - current_category = :low_hr - transitions += 1 - last_transition_delta = last_heart_rate - @heart_rate[i] - last_transition_index = i + if i - last_transition_index >= 25 - 2 * transitions + current_category = :low_hr + transitions += 1 + last_transition_delta = last_heart_rate - @heart_rate[i] + last_transition_index = i + end elsif last_heart_rate < @heart_rate[i] && last_transition_delta < @heart_rate[i] - last_heart_rate # The previously found high segment was wrongly categorized as @@ -320,10 +328,12 @@ module PostRunner else if last_heart_rate < @heart_rate[i] # Low/High transition found. - current_category = :high_hr - transitions += 1 - last_transition_delta = @heart_rate[i] - last_heart_rate - last_transition_index = i + if i - last_transition_index >= 25 + 2 * transitions + current_category = :high_hr + transitions += 1 + last_transition_delta = @heart_rate[i] - last_heart_rate + last_transition_index = i + end elsif last_heart_rate > @heart_rate[i] && last_transition_delta < last_heart_rate - @heart_rate[i] # The previously found low segment was wrongly categorized as |