js_astro
Sample code for astrological calculation written by JavaScript.
This library intent to:
- calculation of major planetary position(geocentric, apparent longitude) for 0-4000 A.D. within 1 arcminute.
- calculation of house cusp longitudes
Requirement
Environment
Newest Browser, but all comments are written in Japanese(Shift-JIS).
Library
Some functions requires spirntf.js, but if you don't want to use function cnv2*, not required.
License
Files in this repository are released under MIT license.
Usage
Calculate for planetary position
Include all libraries, and call calPlanetPositon2 as:
var planetPosition = new Array();
planetPosition = calPlanetPosition2( year, month, day, hour, minute, longitude, latitude );
calPlanetPosition2 returns array of 15 values:
- Julian day
- Planetary Position(Geocentric apparent ecliptic longitude): Sun, Moon, Mercury, Venus, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto
- Lunar Node & apogee Longitude(from approximate osculate orbital elements)
- Longitude of Ascendant, MC(Mid heaven)
- All value is expressed in degree, without Julian day.
Calculate for house cusp longitudes
Include all libraries, and call calHouseCusp2 as:
var cuspLongitudes = new Array();
cuspLongitudes = calHouseCusp2( year, month, day, hour, minute, longitude, latitude, 1 );
Last Argument 1 means Placidus house system.
calHouseCusp2 returns array of house cusp longitude(Index of this array starts 1, not 0).
Important notice
Timezone used in this library is Japan Standard Time(UTC+0900). You may consider to wrapper function to convert your local timezone. I never consider any Daylight Saving Time in past and future.
This library assumes eastern geographical longitude and northern geographical latitude as plus(eg. Tokyo: 139E42 = +139.70, 35N41 = +35.68).
Demonstration
To test this library, try this.
Errata for Leaflet written in Japanese
This library has a leaflet, and this leaflet has some error. Errata is here.