MkApos

This is the gem library which calculates apparent positions of SUn and Moon.

Preparation

This library needs a JPL's DE430 binary file.

Download linux_p1550p2650.430 from ftp://ssd.jpl.nasa.gov/pub/eph/planets/Linux/de430/, and place at a suitable directory.

If neccessary, rename the binary file.

Installation

Add this line to your application's Gemfile:

gem 'mk_apos'

And then execute:

$ bundle

Or install it yourself as:

$ gem install mk_apos

Usage

Instantiation

require "mk_apos"

a = MkApos.new("/path/to/<JPLEPH binary>", "20160914")
a = MkApos.new("/path/to/<JPLEPH binary>", "20160914123456")
a = MkApos.new("/path/to/<JPLEPH binary>", "2016091412345698765")
a = MkApos.new("/path/to/<JPLEPH binary>")

• You can set UTC formatted YYYYMMDD or YYYYMMDDHHMMSS or YYYYMMDDHHMMSSU... as an argument. (U is microsecond)
• If you don't set a second argument, this class considers the system time to have been set as a second argument(UTC).

Calculation

p a.utc.strftime('%Y-%m-%d %H:%M:%S.%3N')
p a.tdb.strftime('%Y-%m-%d %H:%M:%S.%3N')
p a.jd_tdb
p a.sun
p a.moon

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/komasaru/mk_apos.

License

The gem is available as open source under the terms of the MIT License.