Distribution

Playing with ruby science. Fooling around with some distributions. Until now nothing serious

Installation

Add this line to your application's Gemfile:

gem 'distribution'

And then execute:

$ bundle

Or install it yourself as:

$ gem install distribution

other requirements: gnu plotutls.

For mac you can install it with the command:

brew install plotutils

For linux probably there is a package as well.

Status

Usage

Normal Distribution

d = Distribution::Normal.new(mean:0,sigma:1,x:[1,2,3,4])
d.pdf # => [0.24197072451914337, 0.05399096651318806, 0.0044318484119380075, 0.00013383022576488537]
d.get_samples(10,30) # 10 samples with 30 cases each without replacement and discrete
d.get_samples(10,30,true,:continuous) #10 samples with 30 cases each, with replacement and continuous
d.samples # Array of Sample objects

Binomial Distribution

d = Distribution::Binomial.new(n:6,k:1,p:0.3)
d.pmf # [0.30252599999]
d.cdf(3) #P(X<=3)
# => [0.4201749999999991, 0.7443100000000008, 0.9295300000000002, 0.989065, 0.999271, 1.0]
d.symmetric? #=> false
d.to_report
# trials:6
# random variable 0.000e+00
# probability of successes: 0.3
# mean: 1.7999999999999998
# standard deviation: 1.7146428199482244
# skewness: 0.23328473740792177
# kurtosis 2.793650793650794

1. Fork it
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request