WeibullDistribution.C

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//* This file is part of the MOOSE framework
//* https://www.mooseframework.org
//*
//* All rights reserved, see COPYRIGHT for full restrictions
//* https://github.com/idaholab/moose/blob/master/COPYRIGHT
//*
//* Licensed under LGPL 2.1, please see LICENSE for details
//* https://www.gnu.org/licenses/lgpl-2.1.html
 
#include "WeibullDistribution.h"
#include "math.h"
#include "libmesh/utility.h"
 
registerMooseObject("StochasticToolsApp", WeibullDistribution);
 
defineLegacyParams(WeibullDistribution);
 
InputParameters
WeibullDistribution::validParams()
{
  InputParameters params = Distribution::validParams();
  params.addClassDescription("Three-parameter Weibull distribution.");
  params.addRequiredParam<Real>("location", "Location parameter (a or low)");
  params.addRequiredRangeCheckedParam<Real>("scale", "scale > 0", "Scale parameter (b or lambda)");
  params.addRequiredRangeCheckedParam<Real>("shape", "shape > 0", "Shape parameter (c or k)");
  return params;
}
 
WeibullDistribution::WeibullDistribution(const InputParameters & parameters)
  : Distribution(parameters),
    _a(getParam<Real>("location")),
    _b(getParam<Real>("scale")),
    _c(getParam<Real>("shape"))
{
}
 
Real
WeibullDistribution::pdf(const Real & x,
                         const Real & location,
                         const Real & scale,
                         const Real & shape)
{
  if (x <= location)
    return 0.0;
  else
  {
    const Real y = (x - location) / scale;
    return shape / scale * std::pow(y, shape - 1.0) * std::exp(-std::pow(y, shape));
  }
}
 
Real
WeibullDistribution::cdf(const Real & x,
                         const Real & location,
                         const Real & scale,
                         const Real & shape)
{
  if (x <= location)
    return 0.0;
  else
  {
    const Real y = (x - location) / scale;
    return 1.0 - std::exp(-std::pow(y, shape));
  }
}
 
Real
WeibullDistribution::quantile(const Real & p,
                              const Real & location,
                              const Real & scale,
                              const Real & shape)
{
  return location + scale * std::pow(-std::log(1 - p), 1.0 / shape);
}
 
Real
WeibullDistribution::pdf(const Real & x) const
{
  TIME_SECTION(_perf_pdf);
  return pdf(x, _a, _b, _c);
}
 
Real
WeibullDistribution::cdf(const Real & x) const
{
  TIME_SECTION(_perf_cdf);
  return cdf(x, _a, _b, _c);
}
 
Real
WeibullDistribution::quantile(const Real & p) const
{
  TIME_SECTION(_perf_quantile);
  return quantile(p, _a, _b, _c);
}