StringDerivedRandom
Allows one to seed a Ruby Random
object with a seed value that is derived from a given string. This
can be useful for doing "one-in-N" selection for large corpi of identifiers. For example:
rng = StringDerivedRandom.new(document.id.to_s)
rng.rand # => the result is always going to be the same
Installation
Add this line to your application's Gemfile:
gem 'string_derived_random'
And then execute:
$ bundle
Or install it yourself as:
$ gem install string_derived_random
Usage
In your code, use a string identifier (for example a filesystem path, or a user ID) to create a generator,
and then use the generator to emit random values. The generator is a Ruby Random
object.
if StringDerivedRandom.new(file_path).rand(1..200) == 1
apply_processing # will apply to one in 200 file paths
end
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/julik/string_derived_random.
License
The gem is available as open source under the terms of the MIT License.