/* 

  Chi squared inverse dist (generating samples) in Picat.

  From Handbook on probability distributions
  page 81ff

  Note: The ppl_distributions.pi does not support PDF, CDF, quantile 
        for this, just random distribution.

  Cf my Gamble model gamble_chi_squared_inverse_dist.rkt

  This program was created by Hakan Kjellerstrand, hakank@gmail.com
  See also my Picat page: http://www.hakank.org/picat/

*/

import ppl_distributions, ppl_utils.
import util.
% import ordset.

main => go.

/*

  var : g
  Probabilities (truncated):
  39.9905357492975: 0.0001000000000000
  35.668839401379749: 0.0001000000000000
  24.404015137718847: 0.0001000000000000
  22.294754910270829: 0.0001000000000000
  .........
  0.048769054466211: 0.0001000000000000
  0.046681465700159: 0.0001000000000000
  0.045483041021476: 0.0001000000000000
  0.042006457191742: 0.0001000000000000
  mean = 0.496719

*/
go ?=>
  reset_store,
  run_model(10_000,$model,[show_probs_trunc,mean]),
  nl,
  % show_store_lengths,nl,
  % fail,
  nl.
go => true.
  
  
model() =>
  K = 4,
  G = chi_square_inverse_dist(K),
  
  add("g",G).