LatLong

short-FAQ

What does this gem do?

Move lat, long points based on distance and direction.

What else?

For now it's just that, you can check the Usage part for details

What is it for?

I developed it, and use it, to create fake data for my tests when doing mobile apps that depend on location based stuff. Things like people 500 meters away, people within a certain radius, and similar.

I would love to hear about it if you find a better use for it.

IMPORTANT NOTE

There are several ways of calculating distances using geo-coordinates. The different
approaches vary in accuracy, and are used in different scenarios. This gem uses
the [Aviation Formula](http://www.edwilliams.org/avform.htm),
it is the simplest of them all, but it might have big errors
margins when used with distances over 2km. I'm ok with this for now.

Future?

I'm planning on understanding (first things first), and implementing all the other formulas, so they can be used when needed, or otherwise having the gem automatically pick the more accurate depending on the parameters lat, long, distance, direction.

Check Github Issues for backlog and progress.

Installation

Add this line to your application's Gemfile:

gem 'lat_long'

And then execute:

$ bundle

Or install it yourself as:

$ gem install lat_long

Usage

Simply tell distance, distance_unit, direction and get a new location hash


require 'lat_long'

washington_ave_and_17st_nw = LatLong::Point.new 38.892133, (-77.039498)

new_location = washington_ave_and_17st_nw.move 250, :meters, :north

new_location[:lat]  # 38.892133
new_location[:long] # -77.033727

Valid directions:

  • :west
  • :north_west
  • :north
  • :north_east
  • :east
  • :south_east
  • :south
  • :south_west

Valid distance units:

  • :meters
  • :kilometers
  • :miles
  • :feet

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake test 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/matismasters/lat_long. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

License

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