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require 'distribution/gamma/ruby'
require 'distribution/gamma/gsl'
# no statistics2 functions for gamma.
require 'distribution/gamma/java'
module Distribution
# From Wikipedia:
# The gamma distribution is a two-parameter family of
# continuous probability distributions. It has a scale parameter a
# and a shape parameter b.
#
# Calculate pdf, cdf and inverse cdf for Gamma Distribution.
#
module Gamma
extend Distributable
SHORTHAND = 'gamma'
create_distribution_methods
##
# :singleton-method: pdf(x,a,b)
# Returns PDF of of Gamma distribution with +a+ as scale
# parameter and +b+ as shape parameter
##
# :singleton-method: cdf(x,a,b)
# Returns the integral of Gamma distribution with +a+ as scale
# parameter and +b+ as shape parameter
##
# :singleton-method: p_value(qn,a,b)
# Return the upper limit for the integral of a
# gamma distribution which returns +qn+
# with scale +a+ and shape +b+
end
end
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