hash_sample
Implements methods for Hash class for getting weighted random samples with and without replacement, as well as regular random samples
Installation
gem install hash_sample
Usage
require 'hash_sample'
loaded_die = {'1' => 0.1, '2' => 0.1, '3' => 0.1, '4' => 0.1, '5' => 0.1, '6' => 0.5}
p loaded_die.wchoice # "6"
p loaded_die.wchoice(1) # ["6"]
p loaded_die.wchoice(10) # ["4", "6", "3", "3", "2", "2", "1", "6", "4", "6"]
p loaded_die.wsample # 6
p loaded_die.wsample(6) # ["6", "3", "2", "4", "1", "5"]
p loaded_die.wsample(10) # ["2", "6", "1", "3", "4", "5"]
p loaded_die.sample # { '1' => 0.1 }
p loaded_die.sample(6) # {'1' => 0.1, '2' => 0.1, '3' => 0.1, '4' => 0.1, '5' => 0.1, '6' => 0.5}Hash instance methods
hash.sample(n = 1) ⇒ Hash
Choose a random key=>value pair or n random pairs from the hash.
The key=>value pairs are chosen by using random and unique indices in order to ensure that each pair doesn't includes more than once
If the hash is empty it returns an empty hash.
If the hash contains less than n unique keys, the copy of whole hash will be returned, none of keys will be lost due to bad luck.
Returns new Hash containing sample key=>value pairs
hash.wchoice ⇒ Object
hash.wchoice(n) ⇒ Array of n samples.
Weighted random sampling with replacement.
Choose a random key or n random keys from the hash, according to weights defined in hash values.
The samples are drawn by using random and replaced by its copy, so they can be repeated in result.
If the hash is empty the first form returns nil and the second form returns an empty array.
All weights should be Numeric.
Zero or negative weighs will be ignored.
{'_' => 9, 'a' => 1}.wchoice(10) # ["_", "a", "_", "_", "_", "_", "_", "_", "_", "_"]
hash.wsample ⇒ Object
hash.wsample(n) ⇒ Array of n samples.
Weighted random sampling without replacement.
Choose 1 or n distinct random keys from the hash, according to weights defined in hash values. Drawn items are not replaced.
If the hash is empty the first form returns nil and the second form returns an empty array.
All weights should be Numeric.
Zero or negative weighs will be ignored.
{'_' => 9, 'a' => 1}.wchoice(10) # ["_", "a"]
hash.wchoices(n = 1) ⇒ Object
alias for wchoice
hash.wsamples(n = 1) ⇒ Object
alias for wsample
Contributing
- Fork it ( https://github.com/serg123e/hash_sample/fork )
- Create your feature branch (
git checkout -b my-new-feature) - Commit your changes (
git commit -am 'Add some feature') - Push to the branch (
git push origin my-new-feature) - Create a new Pull Request