Class: GitFit::Elevation::Backfill

Inherits:
Object
  • Object
show all
Defined in:
lib/git_fit/elevation/backfill.rb

Constant Summary collapse

SOURCES = 
%w[igpsport xoss strava garmin garmin_cn xingzhe keep].freeze
BATCH_SIZE = 
100

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(db, force: false) ⇒ Backfill

Returns a new instance of Backfill.



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# File 'lib/git_fit/elevation/backfill.rb', line 9

def initialize(db, force: false)
  @db = db
  @force = force
  @updated = 0
  @skipped = 0
  @failed = 0
end

Class Method Details

.filter_low_outliers(altitudes, factor = 2.0) ⇒ Object

Drop only implausibly-low altitude spikes (baro dropouts), leaving the genuinely shifted bulk intact. Lower fence = median - factor1.4826MAD.



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# File 'lib/git_fit/elevation/backfill.rb', line 234

def filter_low_outliers(altitudes, factor = 2.0)
  return altitudes if altitudes.size < 4

  med = median(altitudes)
  m = mad(altitudes)
  return altitudes if m.zero?

  fence = med - factor * 1.4826 * m
  altitudes.reject { |x| x < fence }
end

.mad(values) ⇒ Object 



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# File 'lib/git_fit/elevation/backfill.rb', line 251

def mad(values)
  med = median(values)
  median(values.map { |x| (x - med).abs })
end

.median(values) ⇒ Object 



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# File 'lib/git_fit/elevation/backfill.rb', line 245

def median(values)
  s = values.sort
  n = s.size
  n.odd? ? s[n / 2] : (s[n / 2 - 1] + s[n / 2]) / 2.0
end

Instance Method Details

#call(source = nil) ⇒ Object 



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# File 'lib/git_fit/elevation/backfill.rb', line 17

def call(source = nil)
  sources = source ? [source] : SOURCES
  sources.each do |src|
    backfill_source(src)
  end
  { updated: @updated, skipped: @skipped, failed: @failed }
end