Class: Darian::Time

Inherits:
Object
  • Object
show all
Includes:
DateMethods
Defined in:
lib/darian/time.rb

Overview

Darian Mars calendar time converter.

mars = Darian::Time.from_earth(Time.now)
puts mars
puts mars.month_name

Constant Summary collapse

MARS_TO_EARTH_DAYS = 
1.027491251
EPOCH_OFFSET = 
587744.77817
ROUND_UP_SECOND = 
1/86400

Instance Attribute Summary collapse

Attributes included from DateMethods

#month, #month_of_season, #season, #sol, #sol_of_season, #week_sol, #year

Class Method Summary collapse

Instance Method Summary collapse

Methods included from DateMethods

#month_name, #week_sol_name

Constructor Details

#initialize(sols) ⇒ Time

Create Mars time by sols since 0 year.

It is internal contructor. Use ‘Darian.from_earth`.



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# File 'lib/darian/time.rb', line 51

def initialize(sols)
  sD  = (sols / 334296).floor
  doD = (sols - (sD * 334296)).floor

  sC   = 0
  doC  = doD
  sC   = ((doD - 1) / 66859).floor if doD != 0
  doC -= (sC * 66859) + 1 if sC != 0

  sX  = 0
  doX = doC
  if sC != 0 # century that does not begin with leap day
    sX   = ((doC + 1) / 6686).floor
    doX -= sX * 6686 - 1 if sX != 0
  else
    sX   = (doC / 6686).floor
    doX -= sX * 6686 if sX != 0
  end

  sII = 0
  doII = doX
  if sC != 0 and sX == 0 # decade that does not begin with leap day
    sII   = (doX / 1337).floor
    doII -= sII * 1337 if sII != 0
  else  # 1338, 1337, 1337, 1337 …
    sII   = ((doX - 1) / 1337).floor if doX != 0
    doII -= (sII * 1337 + 1) if sII != 0
  end

  sI  = 0
  doI = doII
  if sII == 0 and (sX != 0 or (sX == 0 and sC == 0))
    sI   = (doII / 669).floor
    doI -= 669 if sI != 0
  else # 668, 669
    sI   = ((doII + 1) / 669).floor
    doI -= 668 if sI != 0
  end

  @year = 500 * sD + 100 * sC + 10 * sX + 2 * sII + sI
  @season = if doI < 167
    0
  elsif doI < 334
    1
  elsif doI < 501
    2
  else
    3
  end
  @sol_of_season   = doI - 167 * @season
  @month_of_season = (@sol_of_season / 28).floor

  @month = @month_of_season + 6 * @season + 1

  @sol      = doI - ((@month - 1) * 28 - @season) + 1
  @week_sol = (@sol - 1) % 7 + 1

  hour = (sols - sols.floor) * 24
  min  = (hour - hour.floor) * 60

  @hour = hour.floor
  @min  = min.floor
  @sec  = ((min - min.floor) * 60).floor
end

Instance Attribute Details

#hour ⇒ Object (readonly)

Returns the value of attribute hour.



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# File 'lib/darian/time.rb', line 34

def hour
  @hour
end

#min ⇒ Object (readonly)

Returns the value of attribute min.



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# File 'lib/darian/time.rb', line 35

def min
  @min
end

#sec ⇒ Object (readonly)

Returns the value of attribute sec.



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# File 'lib/darian/time.rb', line 36

def sec
  @sec
end

Class Method Details

.from_earth(time) ⇒ Object

Return Mars time converted from Earth time.

Darian.from_earth(Time.now)



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# File 'lib/darian/time.rb', line 41

def self.from_earth(time)
  # 719527 is days until 0 year for Unix Epoch
  days = (time.to_i / 86400.0) + 719527
  sols = (days - EPOCH_OFFSET) / MARS_TO_EARTH_DAYS
  self.new(sols)
end

Instance Method Details

#to_date ⇒ Object

Return martian date.



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# File 'lib/darian/time.rb', line 123

def to_date
  ::Darian::Date.new(self)
end

#to_s ⇒ Object

Printable string of martian time.



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# File 'lib/darian/time.rb', line 117

def to_s
  sprintf '%d-%02d-%02d %02d:%02d:%02d',
          @year, @month, @sol, @hour, @min, @sec
end