//                                               -*- C++ -*-
/**
 *  @file  Weibull.hxx
 *  @brief The Weibull distribution
 *
 *  Copyright (C) 2005-2014 Airbus-EDF-Phimeca
 *
 *  This library is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Lesser General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  along with this library.  If not, see <http://www.gnu.org/licenses/>.
 *
 *  @author schueller
 *  @date   2012-02-17 19:35:43 +0100 (Fri, 17 Feb 2012)
 */
#ifndef OPENTURNS_WEIBULL_HXX
#define OPENTURNS_WEIBULL_HXX

#include "ContinuousDistribution.hxx"

BEGIN_NAMESPACE_OPENTURNS

/**
 * @class Weibull
 *
 * The Weibull distribution.
 */
class Weibull
  : public ContinuousDistribution
{
  CLASSNAME;
public:

  enum ParameterSet { ALPHABETA, MUSIGMA };

  typedef Pointer<DistributionImplementation> Implementation;

  /** Default constructor */
  Weibull();

  /** Parameters constructor */
  Weibull(const NumericalScalar arg1,
          const NumericalScalar arg2,
          const NumericalScalar gamma = 0.0,
          const ParameterSet set = ALPHABETA);


  /** Comparison operator */
  Bool operator ==(const Weibull & other) const;

  /** String converter */
  String __repr__() const;
  String __str__(const String & offset = "") const;



  /* Interface inherited from Distribution */

  /** Virtual constructor */
  virtual Weibull * clone() const;

  /** Get one realization of the Weibull distribution */
  NumericalPoint getRealization() const;

  /** Get the DDF of the distribution, i.e. the gradient of its PDF w.r.t. point */
  using ContinuousDistribution::computeDDF;
  NumericalPoint computeDDF(const NumericalPoint & point) const;

  /** Get the PDF of the distribution, i.e. P(point < X < point+dx) = PDF(point)dx + o(dx) */
  using ContinuousDistribution::computePDF;
  NumericalScalar computePDF(const NumericalPoint & point) const;
  using ContinuousDistribution::computeLogPDF;
  NumericalScalar computeLogPDF(const NumericalPoint & point) const;

  /** Get the CDF of the distribution, i.e. P(X <= point) = CDF(point). If tail=true, compute P(X >= point) */
  using ContinuousDistribution::computeCDF;
  NumericalScalar computeCDF(const NumericalPoint & point) const;

  /** Get the gradient of the PDF w.r.t the parameters of the distribution */
  NumericalPoint computePDFGradient(const NumericalPoint & point) const;

  /** Get the gradient of the CDF w.r.t the parameters of the distribution */
  NumericalPoint computeCDFGradient(const NumericalPoint & point) const;

protected:
  /** Set simultaneously alpha and beta to factorize the call to computeRange() */
  void setAlphaBeta(const NumericalScalar alpha,
                    const NumericalScalar beta);

public:

  /** Get the standard deviation of the distribution */
  NumericalPoint getStandardDeviation() const;

  /** Get the skewness of the distribution */
  NumericalPoint getSkewness() const;

  /** Get the kurtosis of the distribution */
  NumericalPoint getKurtosis() const;

  /** Get the raw moments of the standardized distribution */
  NumericalPoint getStandardMoment(const UnsignedLong n) const;

  /** Get the standard representative in the parametric family, associated with the standard moments */
  Implementation getStandardRepresentative() const;

  /** Parameters value and description accessor */
  NumericalPointWithDescriptionCollection getParametersCollection() const;
  using ContinuousDistribution::setParametersCollection;
  void setParametersCollection(const NumericalPointCollection & parametersCollection);

  /* Interface specific to Weibull */

  /** Beta accessor */
  void setBeta(const NumericalScalar beta);
  NumericalScalar getBeta() const;

  /** Alpha accessor */
  void setAlpha(const NumericalScalar alpha);
  NumericalScalar getAlpha() const;

  /** Mu accessor */
  void setMuSigma(const NumericalScalar mu,
                  const NumericalScalar sigma);
  NumericalScalar getMu() const;

  /** Sigma accessor */
  NumericalScalar getSigma() const;

  /** Gamma accessor */
  void setGamma(const NumericalScalar gamma);
  NumericalScalar getGamma() const;

  /** Method save() stores the object through the StorageManager */
  void save(Advocate & adv) const;

  /** Method load() reloads the object from the StorageManager */
  void load(Advocate & adv);

protected:

private:

  /** Compute the mean of the distribution */
  void computeMean() const;

  /** Compute the covariance of the distribution */
  void computeCovariance() const;

  /** Get the quantile of the distribution, i.e the value Xp such that P(X <= Xp) = prob */
  NumericalScalar computeScalarQuantile(const NumericalScalar prob,
                                        const Bool tail = false) const;

  /** Compute the numerical range of the distribution given the parameters values */
  void computeRange();

  /** The main parameter set of the distribution */
  NumericalScalar alpha_;
  NumericalScalar beta_;
  NumericalScalar gamma_;

}; /* class Weibull */

END_NAMESPACE_OPENTURNS

#endif /* OPENTURNS_WEIBULL_HXX */
