Class: Eot

Inherits:
Object
  • Object
show all
Includes:
Math
Defined in:
lib/eot/init.rb,
lib/eot/times.rb,
lib/eot/angles.rb,
lib/eot/deltas.rb,
lib/eot/version.rb,
lib/eot/constants.rb,
lib/eot/utilities.rb,
lib/eot/time_displays.rb,
lib/eot/trigonometric.rb,
lib/eot/angle_displays.rb,
ext/eot/eot.c

Overview

class Eot file = angle_displays.rb

Constant Summary collapse

VERSION = 
'4.1.5'
ARCSEC =

Arc seconds in a degree = 3_600.0

3_600.0
ASD =

Arc seconds in a degree = 3_600.0

3_600.0
DAS2R =

from desktop calculator DAS2R = 4.8481368110953599358991410235795e-6

4.8481368110953599358991410235795e-6
DAY_HOURS =

Hours in a day = 24.0

24.0
DAY_MINUTES =

Minutes in a day = 1_440.0

1_440.0
DAY_SECONDS =

Seconds in a day = 86_400.0

86_400.0
DAYSEC =

Seconds in a day = 86_400.0

86_400.0
DAY_USECS =

Micro Seconds in a day = 86_400_000_000.0

86_400_000_000.0
D2R =

from desktop calculator D2R = 0.017453292519943295769236907684886

0.017453292519943295769236907684886
DJ00 =

Reference epoch (J2000.0), Julian Date Default Julian Number = 2451545.0

2_451_545.0
DJC =

Days per Julian century = 36525.0

36_525.0
DT2000 =

Default DateTime = DateTime.new( 2000, 01, 01, 12, 00, 00, “+00:00” )

DateTime.new(2000, 01, 01, 12, 00, 00, '+00:00')
PI =

from desktop calculator PI = 3.1415926535897932384626433832795

3.1415926535897932384626433832795
P2 =

2Pi from Math module = Math::PI * 2.0

PI * 2.0
R2D =

from desktop calculator R2D = 57.295779513082320876798154814105

57.295779513082320876798154814105
RTD =

from desktop calculator RTD = 0.015915494309189533576888376337251

0.015915494309189533576888376337251
SM =

from desktop calculator Sidereal minutes = 4.0 / 1.0027379093507953456536618754278

4.0 / 1.0027379093507953456536618754278

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Eot

From init.rb: Initialize to set attributes You may use GeoLatLng to set up @latitude and @longitude



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# File 'lib/eot/init.rb', line 55

def initialize
  @geo = GeoLatLng.new
  @addr = @geo.default_int
  @geo.addr = @addr
  @ajd = DateTime.now.to_time.utc.to_datetime.jd.to_f
  @date, @jd = ajd_to_datetime(@ajd), @ajd
  @geo.set_coordinates
  # queries could excede quotas or you get disconnected.
  @geo.lat.zero? ? @latitude = 0.0 : @latitude = @geo.lat
  @geo.lng.zero? ? @longitude = 0.0 : @longitude = @geo.lng
end

Instance Attribute Details

#addr ⇒ Object

From init.rb: address used for GeoLatLng.addr



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# File 'lib/eot/init.rb', line 5

def addr
  @addr
end

#ajd ⇒ Object

From init.rb: Astronomical Julian Day Number is an instance of DateTime class. ajd or jd. Use ajd for time now and jd for suntimes. Initially



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# File 'lib/eot/init.rb', line 11

def ajd
  @ajd
end

#date ⇒ Object

From init.rb: When new Eot class is initialized @date = ajd_to_datetime(@ajd)



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# File 'lib/eot/init.rb', line 22

def date
  @date
end

#jd ⇒ Object

From init.rb: Julian Day Number is an instance of DateTime class. When new Eot class is initialized @jd = @ajd



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# File 'lib/eot/init.rb', line 27

def jd
  @jd
end

#latitude ⇒ Object

From init.rb: Latitude input is an instance of Float class. When new Eot class is initialized @latitude = 0.0 if GeoLatLng class can’t set it.



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# File 'lib/eot/init.rb', line 33

def latitude
  @latitude
end

#longitude ⇒ Object

From init.rb: Longitude input is an instance of Float class. When new Eot class is initialized @longitude = 0.0 if GeoLatLng class can’t set it.



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# File 'lib/eot/init.rb', line 39

def longitude
  @longitude
end

#ma ⇒ Object

From init.rb: Mean Anomaly gets called a lot so class attribute saves it.



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# File 'lib/eot/init.rb', line 50

def ma
  @ma
end

#ta ⇒ Object

From init.rb: JCT gets called a lot so class attribute it. Setting @ajd will set this and @ma



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# File 'lib/eot/init.rb', line 45

def ta
  @ta
end

Instance Method Details

#ajd_to_datetime(ajd) ⇒ Object

From times.rb: Pass in an AJD number Returns a DateTime object



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# File 'lib/eot/times.rb', line 6

def ajd_to_datetime(ajd)
  DateTime.jd(ajd + 0.5)
end

#al(vma, vt, vo) ⇒ Object 



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# File 'ext/eot/eot.c', line 30

VALUE func_al(VALUE klass, VALUE vma, VALUE vt, VALUE vo) {
  rb_ivar_set(klass, id_status, INT2FIX(0));
  return DBL2NUM(alSun(NUM2DBL(vma), NUM2DBL(vt), NUM2DBL(vo)));
}

#al_sun ⇒ Object Also known as: apparent_longitude, alsun

From angles.rb: Apparent solar longitude = true longitude - aberation



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# File 'lib/eot/angles.rb', line 6

def al_sun
  Celes.anp(al(@ma, @ta, Celes.faom03(@ta)))
end

#angle_delta_epsilon ⇒ Object Also known as: delta_epsilon

From deltas.rb: delta epsilon component of equation of equinox



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# File 'lib/eot/deltas.rb', line 6

def angle_delta_epsilon
  Celes.nut06a(@ajd, 0)[1]
end

#angle_delta_oblique ⇒ Object Also known as: delta_t_ecliptic, delta_oblique

From deltas.rb: one time component to total equation of time



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# File 'lib/eot/deltas.rb', line 13

def angle_delta_oblique
  al_sun - ra_sun
end

#angle_delta_orbit ⇒ Object Also known as: delta_t_elliptic, delta_orbit

From angles.rb: one time component to total equation of time



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# File 'lib/eot/deltas.rb', line 21

def angle_delta_orbit
  -1.0 * eqc(@ma, @ta)
end

#angle_delta_psi ⇒ Object Also known as: delta_psi

From angles.rb: component of equation of equinox



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# File 'lib/eot/deltas.rb', line 29

def angle_delta_psi
  Celes.nut06a(@ajd, 0)[0]
end

#angle_equation_of_time ⇒ Object Also known as: eot

From angles.rb: total equation of time



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# File 'lib/eot/deltas.rb', line 36

def angle_equation_of_time
  delta_orbit + delta_oblique
end

#center ⇒ Object Also known as: equation_of_center

From angles.rb: equation of centre added to mean anomaly to get true anomaly.



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# File 'lib/eot/angles.rb', line 15

def center
  eqc(@ma, @ta)
end

#check_jd_nil(jd = DJ00) ⇒ Object

From utilities.rb: A check for default J2000 sets default when arg is nil



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# File 'lib/eot/utilities.rb', line 7

def check_jd_nil(jd = DJ00)
  jd.nil? ? DJ00 : jd
end

#check_jd_zero(jd = DJ00) ⇒ Object

From utilities.rb: A check for default J2000 sets default when arg is zero



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# File 'lib/eot/utilities.rb', line 14

def check_jd_zero(jd = DJ00)
  jd == 0 ? DJ00 : check_jd_nil(jd)
end

#check_t_nil(dt = DT2000) ⇒ Object

From utilities.rb: A check for default DT2000 sets default when arg is nil



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# File 'lib/eot/utilities.rb', line 21

def check_t_nil(dt = DT2000)
  dt.nil? ? DT2000 : dt
end

#check_t_zero(dt = DT2000) ⇒ Object

From utilities.rb: A check for default DT2000 sets default when arg is zero



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# File 'lib/eot/utilities.rb', line 28

def check_t_zero(dt = DT2000)
  dt == 0 ? DT2000 : check_t_nil(dt)
end

#cos_al_sun(vals) ⇒ Object 



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# File 'ext/eot/eot.c', line 40

VALUE func_cos_al_sun(VALUE klass, VALUE vals) {
  rb_ivar_set(klass, id_status, INT2FIX(0));
  return DBL2NUM(cos_al_sun(NUM2DBL(vals)));
}

#cos_dec_sun(vds) ⇒ Object 



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# File 'ext/eot/eot.c', line 75

VALUE func_cos_dec_sun(VALUE klass, VALUE vds) {
  rb_ivar_set(klass, id_status, INT2FIX(0));
  return DBL2NUM(cos_dec_sun(NUM2DBL(vds)));
}

#cos_lat(vlat) ⇒ Object 



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# File 'ext/eot/eot.c', line 85

VALUE func_cos_lat(VALUE klass, VALUE vlat) {
  rb_ivar_set(klass, id_status, INT2FIX(0));
  return DBL2NUM(cos_lat(NUM2DBL(vlat)));
}

#cos_tl_sun(vtls) ⇒ Object 



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# File 'ext/eot/eot.c', line 45

VALUE func_cos_tl_sun(VALUE klass, VALUE vtls) {
  rb_ivar_set(klass, id_status, INT2FIX(0));
  return DBL2NUM(cos_al_sun(NUM2DBL(vtls)));
}

#cos_to_earth(vtoe) ⇒ Object 



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# File 'ext/eot/eot.c', line 50

VALUE func_cos_to_earth(VALUE klass, VALUE vtoe) {
  rb_ivar_set(klass, id_status, INT2FIX(0));
  return DBL2NUM(cos_to_earth(NUM2DBL(vtoe)));
}

#cosine_al_sun ⇒ Object Also known as: cosine_apparent_longitude, cosalsun

From trigometric.rb: cosine apparent longitude could be useful when dividing



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# File 'lib/eot/trigonometric.rb', line 7

def cosine_al_sun
  cos_al_sun(al(@ma, @ta, Celes.faom03(@ta)))
end

#cosine_tl_sun ⇒ Object Also known as: cosine_true_longitude

From trigometric.rb: cosine true longitude used in solar right ascension



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# File 'lib/eot/trigonometric.rb', line 16

def cosine_tl_sun
  cos_tl_sun(tl(@ma, @ta))
end

#cosine_to_earth ⇒ Object Also known as: cosine_true_obliquity

From trigometric.rb: cosine true obliquity used in solar right ascension and equation of equinox



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# File 'lib/eot/trigonometric.rb', line 24

def cosine_to_earth
  cos_to_earth(Celes.nut06a(@ajd, 0)[1] + Celes.obl06(@ajd, 0))
end

#cosZ(vz) ⇒ Object 



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# File 'ext/eot/eot.c', line 35

VALUE func_cosZ(VALUE klass, VALUE vz) {
  rb_ivar_set(klass, id_status, INT2FIX(0));
  return DBL2NUM(cosZ(NUM2DBL(vz)));
}

#dec_sun ⇒ Object Also known as: declination

From angles.rb: solar declination



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# File 'lib/eot/angles.rb', line 22

def dec_sun
  asin(sin(Celes.nut06a(@ajd, 0)[1] + Celes.obl06(@ajd, 0)) *
          sin(al(@ma, @ta, Celes.faom03(@ta))))
end

#deg_string(sgn, d, m, s, ds) ⇒ Object 



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# File 'lib/eot/angle_displays.rb', line 3

def deg_string(sgn, d, m, s, ds)
  sgn +
  format('%03d', d) +
          ':' +
  format('%02d', m) +
          ':' +
  format('%02d', s) +
          '.' +
  format('%3.3d', ds)
end

#degrees_to_s(radians = 0.0) ⇒ Object

From displays.rb String formatter for d:m:s display



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# File 'lib/eot/angle_displays.rb', line 16

def degrees_to_s(radians = 0.0)
  radians.nil? ? radians = 0.0 : radians
  radians < 0 ? sign = '-' : sign = '+'
  deg = (radians * R2D).abs
  int_deg = Integer(deg)
  min = 60.0 * (deg - int_deg)
  int_min = Integer(min)
  sec = 60.0 * (min - int_min)
  int_sec = Integer(sec)
  int_ds = Integer(1000.0 * (sec - int_sec))
  deg_string(sign, int_deg, int_min, int_sec, int_ds)
end

#dt_parts(val) ⇒ Object 



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# File 'lib/eot/time_displays.rb', line 78

def dt_parts(val)
  h = val.hour
  m  = val.min
  s  = val.sec
  is = Integer(s)
  ds = Integer((s - is).round(3) * 1000.0)
  [h, m, is, ds]
end

#eccentricity_earth ⇒ Object Also known as: eccentricity_earth_orbit

From angles.rb: eccentricity of elliptical Earth orbit around Sun Horners’ calculation method



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# File 'lib/eot/angles.rb', line 31

def eccentricity_earth
  eoe(@ta)
end

#eoe(vt) ⇒ Object 



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# File 'ext/eot/eot.c', line 15

VALUE func_eoe(VALUE klass, VALUE vt) {
  rb_ivar_set(klass, id_status, INT2FIX(0));
  return DBL2NUM(eoe(NUM2DBL(vt)));
}

#eot_jd ⇒ Object

From times.rb: Uses @ajd attribute Returns EOT as an AJD Julian number



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# File 'lib/eot/times.rb', line 13

def eot_jd
  time_eot / DAY_MINUTES
end

#eq_of_equinox ⇒ Object

From angles.rb: equation of equinox used for true longitude of Aries Depricated by Celes.gst06a()



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# File 'lib/eot/angles.rb', line 40

def eq_of_equinox
  cos(Celes.nut06a(@ajd, 0)[1] +
      Celes.obl06(@ajd, 0)) *
      Celes.nut06a(@ajd, 0)[0]
end

#eqc(vma, vt) ⇒ Object 



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# File 'ext/eot/eot.c', line 20

VALUE func_eqc(VALUE klass, VALUE vma, VALUE vt) {
 rb_ivar_set(klass, id_status, INT2FIX(0));
 return DBL2NUM(eqc(NUM2DBL(vma), NUM2DBL(vt)));  
}

#float_parts(val) ⇒ Object 



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# File 'lib/eot/time_displays.rb', line 87

def float_parts(val)
  hours = Integer(val % DAY_HOURS)
  mins = 60.0 * (val % DAY_HOURS - hours)
  imins = Integer(mins)
  secs = 60.0 * (mins - imins)
  isecs = Integer(secs)
  ds    = Integer((secs - isecs).round(3) * 1000.0)
  [hours, imins, isecs, ds]
end

#format_time(h, m, s, ds) ⇒ Object 



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# File 'lib/eot/time_displays.rb', line 68

def format_time(h, m, s, ds)
  format('%02d', h)   +
               ':' +
  format('%02d', m) +
               ':' +
  format('%02d', s) +
               '.' +
  format('%3.3d', ds)
end

#gml_sun ⇒ Object Also known as: geometric_mean_longitude

From angles.rb: angle geometric mean longitude needed to get true longitude for low accuracy.



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# File 'lib/eot/angles.rb', line 49

def gml_sun
  ml(@ta)
end

#ha_sun ⇒ Object Also known as: horizon_angle

From angles.rb: horizon angle for provided geo coordinates used for angles from transit to horizons



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# File 'lib/eot/angles.rb', line 57

def ha_sun
  zenith   = 90.8333 # use other zeniths here for non commercial
  top      = cosZ(zenith) - sin_dec_sun(dec_sun) * sin_lat(@latitude * D2R)
  bottom   = cos_dec_sun(dec_sun) * cos_lat(@latitude * D2R)
  t_cosine = top / bottom
  t_cosine > 1.0 || t_cosine < -1.0 ? cos = 1.0 : cos = t_cosine
  acos(cos)
end

#local_noon_dt ⇒ Object

From times.rb: Uses @ajd and @longitude attributes Returns DateTime object of local noon or solar transit



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# File 'lib/eot/times.rb', line 20

def local_noon_dt
  ajd_to_datetime(@ajd - @longitude / 360.0 - eot_jd)
end

#ma_sun ⇒ Object Also known as: mean_anomaly

From angles.rb: angle of Suns’ mean anomaly calculated in nutation.rb via celes function sets ta attribute for the rest the methods needing it. used in equation of time and to get true anomaly true longitude via center equation



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# File 'lib/eot/angles.rb', line 73

def ma_sun
  @ta = (@ajd - DJ00) / DJC
  @ma = Celes.falp03(@ta)
end

#mean_local_noon_dt ⇒ Object

From times.rb: Uses @ajd and @longitude attributes Returns DateTime object of local mean noon or solar transit



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# File 'lib/eot/times.rb', line 27

def mean_local_noon_dt
  ajd_to_datetime(@ajd - @longitude / 360.0)
end

#ml(vt) ⇒ Object 



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# File 'ext/eot/eot.c', line 10

VALUE func_ml(VALUE klass, VALUE vt) {
  rb_ivar_set(klass, id_status, INT2FIX(0));
  return DBL2NUM(mlSun(NUM2DBL(vt)));
}

#ml_aries ⇒ Object Also known as: mean_longitude_aries

From angles.rb: Mean equinox point where right ascension is measured from as zero hours. # see www.iausofa.org/publications/aas04.pdf



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# File 'lib/eot/angles.rb', line 82

def ml_aries
  dt = 67.184
  tt = @ajd + dt / 86_400.0
  Celes.gmst06(@ajd, 0, tt, 0)
end

#mo_earth ⇒ Object Also known as: mean_obliquity_of_ecliptic, mean_obliquity

From angles.rb: mean obliquity of Earth



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# File 'lib/eot/angles.rb', line 91

def mo_earth
  Celes.obl06(@ajd, 0)
end

#mod_360(x = 0.0) ⇒ Object Also known as: truncate

From utilities.rb: Keeps large angles in range of 360.0 aliased by truncate



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# File 'lib/eot/utilities.rb', line 35

def mod_360(x = 0.0)
  x.nil? ? x = 0.0 : x
  360.0 * (x / 360.0 - Integer(x / 360.0))
end

#now ⇒ Object

From times.rb: sets @ajd to DateTime.now Returns EOT (equation of time) now in decimal minutes form



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# File 'lib/eot/times.rb', line 34

def now
  @ajd = DateTime.now.to_time.utc.to_datetime.ajd
  @ta = (@ajd - DJ00) / DJC
  time_eot
end

#omega ⇒ Object

From angles.rb: omega is a component of nutation and used in apparent longitude omega is the longitude of the mean ascending node of the lunar orbit on the ecliptic plane measured from the mean equinox of date.



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# File 'lib/eot/angles.rb', line 102

def omega
  Celes.faom03(@ta)
end

#ra_sun ⇒ Object Also known as: right_ascension

From angles.rb: solar right ascension



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# File 'lib/eot/angles.rb', line 108

def ra_sun
  y0 = sin(al(@ma, @ta, Celes.faom03(@ta))) * cos(Celes.nut06a(@ajd, 0)[1] +
       Celes.obl06(@ajd, 0))
  Celes.anp(PI + atan2(-y0, -cos(al(@ma, @ta, Celes.faom03(@ta)))))
end

#show_minutes(min = 0.0) ⇒ Object

From displays.rb String formatter for + and - time



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# File 'lib/eot/time_displays.rb', line 5

def show_minutes(min = 0.0)
  min.nil? ? min = 0.0 : min
  time = Time.utc(1, 1, 1, 0, 0, 0, 0.0)
  time += (min.abs * 60.0)
  sign = sign_min(min)
  time.strftime("#{sign}%M:%S.%3N")
end

#show_now(now = now(Time.now.utc)) ⇒ Object

From displays.rb String for time now



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# File 'lib/eot/time_displays.rb', line 15

def show_now(now = now(Time.now.utc))
  show_minutes(now)
end

#sign_min(min) ⇒ Object 



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# File 'lib/eot/time_displays.rb', line 35

def sign_min(min)
  if min < 0.0
    sign = '-'
  else
    sign = '+'
  end
  sign
end

#sin_al_sun(vals) ⇒ Object 



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# File 'ext/eot/eot.c', line 55

VALUE func_sin_al_sun(VALUE klass, VALUE vals) {
  rb_ivar_set(klass, id_status, INT2FIX(0));
  return DBL2NUM(sin_al_sun(NUM2DBL(vals)));
}

#sin_dec_sun(vds) ⇒ Object 



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# File 'ext/eot/eot.c', line 70

VALUE func_sin_dec_sun(VALUE klass, VALUE vds) {
  rb_ivar_set(klass, id_status, INT2FIX(0));
  return DBL2NUM(sin_dec_sun(NUM2DBL(vds)));
}

#sin_lat(vlat) ⇒ Object 



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# File 'ext/eot/eot.c', line 80

VALUE func_sin_lat(VALUE klass, VALUE vlat) {
  rb_ivar_set(klass, id_status, INT2FIX(0));
  return DBL2NUM(sin_lat(NUM2DBL(vlat)));
}

#sin_tl_sun(vtls) ⇒ Object 



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# File 'ext/eot/eot.c', line 60

VALUE func_sin_tl_sun(VALUE klass, VALUE vtls) {
  rb_ivar_set(klass, id_status, INT2FIX(0));
  return DBL2NUM(sin_al_sun(NUM2DBL(vtls)));
}

#sin_to_earth(vtoe) ⇒ Object 



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# File 'ext/eot/eot.c', line 65

VALUE func_sin_to_earth(VALUE klass, VALUE vtoe) {
  rb_ivar_set(klass, id_status, INT2FIX(0));
  return DBL2NUM(sin_to_earth(NUM2DBL(vtoe)));
}

#sine_al_sun ⇒ Object Also known as: sine_apparent_longitude

From trigometric.rb: sine apparent longitude used in solar declination



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# File 'lib/eot/trigonometric.rb', line 32

def sine_al_sun
  sin_al_sun(al(@ma, @ta, Celes.faom03(@ta)))
end

#sine_tl_sun ⇒ Object Also known as: sine_true_longitude

From trigometric.rb: sine true longitude used in solar right ascension



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# File 'lib/eot/trigonometric.rb', line 40

def sine_tl_sun
  sin_tl_sun(tl(@ma, @ta))
end

#sine_to_earth ⇒ Object

From trigometric.rb: sine true obliquity angle of Earth used in solar declination



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# File 'lib/eot/trigonometric.rb', line 48

def sine_to_earth
  sin_to_earth(Celes.nut06a(@ajd, 0)[1] + Celes.obl06(@ajd, 0))
end

#string_al_sun ⇒ Object Also known as: apparent_longitude_string

From displays.rb String format of apparent longitude



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# File 'lib/eot/angle_displays.rb', line 31

def string_al_sun
  degrees_to_s(al_sun)
end

#string_day_fraction_to_time(jpd_time = 0.0) ⇒ Object Also known as: julian_period_day_fraction_to_time

From displays.rb String formatter for fraction of Julian day number



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# File 'lib/eot/time_displays.rb', line 21

def string_day_fraction_to_time(jpd_time = 0.0)
  jpd_time.nil? ? jpd_time = 0.0 : jpd_time
  fraction = jpd_time + 0.5 - Integer(jpd_time)
  h = Integer(fraction * DAY_HOURS)
  m = Integer((fraction - h / DAY_HOURS) * DAY_MINUTES)
  s = Integer((fraction - h / 24.0 - m / DAY_MINUTES) * DAY_SECONDS)
  format('%02d', h)   +
  ':'              +
  format('%02d', m) +
  ':'              +
  format('%02d', s)
end

#string_dec_sun ⇒ Object Also known as: declination_string

From displays.rb String format of declination



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# File 'lib/eot/angle_displays.rb', line 38

def string_dec_sun
  degrees_to_s(dec_sun)
end

#string_delta_oblique ⇒ Object

From displays.rb String format for delta oblique



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# File 'lib/eot/angle_displays.rb', line 45

def string_delta_oblique
  show_minutes(delta_oblique)
end

#string_delta_orbit ⇒ Object

From displays.rb String format for delta orbit



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# File 'lib/eot/angle_displays.rb', line 51

def string_delta_orbit
  show_minutes(delta_orbit)
end

#string_eot ⇒ Object Also known as: display_equation_of_time

From displays.rb Equation of time output for minutes and seconds



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# File 'lib/eot/time_displays.rb', line 46

def string_eot
  min_eot = time_eot
  sign = sign_min(min_eot)
  eot = min_eot.abs
  minutes = Integer(eot)
  seconds = (eot - minutes) * 60.0
  decimal_seconds = (seconds - Integer(seconds)) * 100.0
  min = format('%02d', minutes)
  sec = format('%02d', seconds)
  dec_sec = format('%01d', decimal_seconds)
  sign << min << 'm, ' << sec << '.' << dec_sec << 's'
end

#string_eqc ⇒ Object

From displays.rb String format for centre



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# File 'lib/eot/angle_displays.rb', line 57

def string_eqc
  degrees_to_s(center)
end

#string_jd_to_date(jd = DJ00) ⇒ Object Also known as: jd_to_date_string

From displays.rb String format conversion of jd to date



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# File 'lib/eot/time_displays.rb', line 62

def string_jd_to_date(jd = DJ00)
  jd = check_jd_zero(jd)
  Date.jd(jd).to_s
end

#string_ma_sun ⇒ Object Also known as: mean_anomaly_string

From displays.rb String format of mean anomaly



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# File 'lib/eot/angle_displays.rb', line 63

def string_ma_sun
  degrees_to_s(@ma)
end

#string_ra_sun ⇒ Object Also known as: right_ascension_string

From displays.rb String format of right ascension



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# File 'lib/eot/angle_displays.rb', line 70

def string_ra_sun
  degrees_to_s(ra_sun)
end

#string_ta_sun ⇒ Object Also known as: true_anomaly_string

From displays.rb String format of true anomaly



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# File 'lib/eot/angle_displays.rb', line 77

def string_ta_sun
  degrees_to_s(ta_sun)
end

#string_time(dt = DT2000) ⇒ Object Also known as: display_time_string

From displays.rb String formatter for h:m:s display



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# File 'lib/eot/time_displays.rb', line 99

def string_time(dt = DT2000)
  dt = check_t_zero(dt)
  dt.class == DateTime ? ta = dt_parts(dt) : ta = float_parts(dt)
  format_time(ta[0], ta[1], ta[2], ta[3])
end

#string_tl_sun ⇒ Object Also known as: true_longitude_string

From displays.rb String format of true longitude



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# File 'lib/eot/angle_displays.rb', line 84

def string_tl_sun
  degrees_to_s(tl_sun)
end

#string_to_earth ⇒ Object Also known as: true_obliquity_string

From displays.rb String format of true obliquity



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# File 'lib/eot/angle_displays.rb', line 91

def string_to_earth
  degrees_to_s(to_earth)
end

#sunrise_dt ⇒ Object

From times.rb: Uses @ajd attribute Returns a DateTime object of local sunrise



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# File 'lib/eot/times.rb', line 43

def sunrise_dt
  ajd_to_datetime(sunrise_jd)
end

#sunrise_jd ⇒ Object

From times.rb: Uses @ajd attribute Returns Sunrise as a Julian Day Number



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# File 'lib/eot/times.rb', line 50

def sunrise_jd
  local_noon_dt.ajd - ha_sun / P2
end

#sunset_dt ⇒ Object

From times.rb: Uses @ajd attribute Returns a DateTime object of local sunset



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# File 'lib/eot/times.rb', line 57

def sunset_dt
  ajd_to_datetime(sunset_jd)
end

#sunset_jd ⇒ Object

From times.rb: Uses @ajd attribute Returns Sunset as a Julian Day Number



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# File 'lib/eot/times.rb', line 64

def sunset_jd
  local_noon_dt.ajd + ha_sun / P2
end

#ta_sun ⇒ Object Also known as: true_anomaly

From angles.rb: angle true anomaly used in equation of time



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# File 'lib/eot/angles.rb', line 118

def ta_sun
  Celes.anp(@ma + eqc(@ma, @ta))
end

#time_delta_oblique ⇒ Object

From times.rb: Uses @ajd attribute Returns Oblique component of EOT in decimal minutes time



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# File 'lib/eot/times.rb', line 71

def time_delta_oblique
  (tl_sun - ra_sun) * R2D * SM
end

#time_delta_orbit ⇒ Object

From times.rb: Uses @ajd attribute Returns Orbit component of EOT in decimal minutes time



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# File 'lib/eot/times.rb', line 78

def time_delta_orbit
  (@ma - ta_sun) * R2D * SM
end

#time_eot ⇒ Object

From times.rb: Uses @ajd attribute Returns EOT as a float for decimal minutes time



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# File 'lib/eot/times.rb', line 85

def time_eot
  eot * R2D * SM
end

#time_julian_century ⇒ Object Also known as: time_julian_centurey

From times.rb: All calculations with ( ta ) were based on this. Julian Century Time is a fractional century Julian Day Number DJ00 is subtracted from the JDN or AJDN and then divided by days in a Julian Century. Deprecated



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# File 'lib/eot/times.rb', line 95

def time_julian_century
  t1 = (@ajd - DJ00) / DJC
  # t2 = t1 * t1
  # t3 = t1 * t2
  # t4 = t2 * t2
  # t5 = t2 * t3
  # t6 = t3 * t3
  # t7 = t3 * t4
  # t8 = t4 * t4
  # t9 = t4 * t5
  # t10 = t5 * t5
  # @ta = [ t1, t2, t3, t4, t5, t6, t7, t8, t9, t10 ]
  @ta = t1
end

#tl(vma, vt) ⇒ Object 



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# File 'ext/eot/eot.c', line 25

VALUE func_tl(VALUE klass, VALUE vma, VALUE vt) {
  rb_ivar_set(klass, id_status, INT2FIX(0));
  return DBL2NUM(tlSun(NUM2DBL(vma), NUM2DBL(vt)));
}

#tl_aries ⇒ Object Also known as: true_longitude_aries

From angles.rb: true longitude of equinox ‘first point of aries’ considers nutation



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# File 'lib/eot/angles.rb', line 126

def tl_aries
  dt = 67.184
  tt = @ajd + dt / 86_400.0
  Celes.gst06a(@ajd, 0, tt, 0)
end

#tl_sun ⇒ Object Also known as: true_longitude, ecliptic_longitude, lambda

From angles.rb: angle of true longitude sun used in equation of time



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# File 'lib/eot/angles.rb', line 136

def tl_sun
  tl(@ma, @ta)
end

#to_earth ⇒ Object Also known as: obliquity_correction, true_obliquity, toearth

From angles.rb: true obliquity considers nutation



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# File 'lib/eot/angles.rb', line 145

def to_earth
  Celes.nut06a(@ajd, 0)[1] + Celes.obl06(@ajd, 0)
end