Module: AstroChart::Pure

Defined in:
lib/astro_chart/pure.rb,
lib/astro_chart/pure/core.rb,
lib/astro_chart/pure/moon.rb,
lib/astro_chart/pure/pluto.rb,
lib/astro_chart/pure/houses.rb,
lib/astro_chart/pure/vsop87.rb,
lib/astro_chart/pure/moon_elp.rb,
lib/astro_chart/pure/vsop87_data.rb

Overview

Pure-Ruby ephemeris backend (MIT-safe, zero external dependencies).

Front-facing API mirrors the Swiss Ephemeris C extension (AstroChart::Ext):

Pure.julday(year, month, day, hour)      -> JD(UT) Float
Pure.calc_ut(jd_ut, planet_id)           -> apparent ecliptic longitude (deg, 0-360)
Pure.houses(jd_ut, lat, lon, hsys = "P") -> { "cusps" => [12], "ascendant" => f, "mc" => f }

planet_id follows the SE convention:

SUN=0 MOON=1 MERCURY=2 VENUS=3 MARS=4 JUPITER=5 SATURN=6
URANUS=7 NEPTUNE=8 PLUTO=9 TRUE_NODE=11

Defined Under Namespace

Modules: Core, Houses, Moon, Pluto, Vsop87, Vsop87Data

Constant Summary collapse

VSOP87_PLANET_IDS =

planet_id (SE convention) -> handled by which pure module

[0, 2, 3, 4, 5, 6, 7, 8].freeze
MOON_ID = 
1
PLUTO_ID = 
9
TRUE_NODE_ID = 
11

Class Method Summary collapse

Class Method Details

.calc_ut(jd_ut, planet_id) ⇒ Object

Apparent ecliptic longitude (degrees, [0, 360)) for the given body.



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# File 'lib/astro_chart/pure.rb', line 35

def calc_ut(jd_ut, planet_id)
  case planet_id
  when *VSOP87_PLANET_IDS
    Vsop87.apparent_longitude(planet_id, jd_ut)
  when MOON_ID
    Moon.apparent_longitude(jd_ut)
  when PLUTO_ID
    Pluto.apparent_longitude(jd_ut)
  when TRUE_NODE_ID
    Moon.true_node(jd_ut)
  else
    raise ArgumentError,
          "unsupported planet_id #{planet_id.inspect} " \
          "(supported: 0-9 and 11/TRUE_NODE, SE convention)"
  end
end

.ecliptic_latlon(jd_ut, planet_id) ⇒ Object

Apparent geocentric ecliptic [longitude, latitude] in degrees for the Sun, Moon, VSOP87 planets and Pluto (nodes are not physical bodies).



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# File 'lib/astro_chart/pure.rb', line 54

def ecliptic_latlon(jd_ut, planet_id)
  case planet_id
  when *VSOP87_PLANET_IDS
    Vsop87.apparent_ecliptic(planet_id, jd_ut)
  when MOON_ID
    Moon.apparent_ecliptic(jd_ut)
  when PLUTO_ID
    Pluto.apparent_ecliptic(jd_ut)
  else
    raise ArgumentError,
          "ecliptic_latlon unsupported planet_id #{planet_id.inspect} " \
          "(supported: Sun 0, planets 2-8, Moon, Pluto)"
  end
end

.houses(jd_ut, latitude, longitude, hsys = "P") ⇒ Object

House cusps + ascendant + MC. Placidus ("P") and Whole Sign ("W"). hsys accepts "P"/"W" or 80/87 (ord values) to mirror the C extension's int argument.



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# File 'lib/astro_chart/pure.rb', line 71

def houses(jd_ut, latitude, longitude, hsys = "P")
  case hsys
  when "P", 80 then Houses.calc(jd_ut, latitude, longitude, "P")
  when "W", 87 then Houses.calc(jd_ut, latitude, longitude, "W")
  when "E", 69 then Houses.calc(jd_ut, latitude, longitude, "E")
  when "O", 79 then Houses.calc(jd_ut, latitude, longitude, "O")
  else
    raise ArgumentError,
          "unsupported house system #{hsys.inspect} " \
          "(pure backend supports Placidus \"P\"/80, Whole Sign \"W\"/87, " \
          "Equal \"E\"/69 and Porphyry \"O\"/79)"
  end
end

.julday(year, month, day, hour) ⇒ Object

Convert calendar date/time (UT) to Julian Day number.



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# File 'lib/astro_chart/pure.rb', line 30

def julday(year, month, day, hour)
  Core.julday(year, month, day, hour)
end