StochasticTools::MultiDimPolynomialGenerator Class Reference

Class containing functionalitties to generate the degress of the 1D Polynomials within every term of a multi-dimensional polynomial. More...

#include <MultiDimPolynomialGenerator.h>

Public Member Functions
	MultiDimPolynomialGenerator ()
	~MultiDimPolynomialGenerator ()=default

Static Public Member Functions
static std::vector< std::vector< unsigned int > >	generateTuple (unsigned int n_dims, unsigned int max_degree, bool include_bias=true)
	Function computing for computing _tuple Example for ndim = 3, order = 4: | 0 | 1 0 0 | 2 1 1 0 0 0 | 3 2 2 1 1 1 0 0 0 0 | | 0 | 0 1 0 | 0 1 0 2 1 0 | 0 1 0 2 1 0 3 2 1 0 | | 0 | 0 0 1 | 0 0 1 0 1 2 | 0 0 1 0 1 2 0 1 2 3 |.
static bool	sortTuple (const std::vector< unsigned int > &first, const std::vector< unsigned int > &second)
	Tuple sorter function.

Detailed Description

Class containing functionalitties to generate the degress of the 1D Polynomials within every term of a multi-dimensional polynomial.

Definition at line 26 of file MultiDimPolynomialGenerator.h.

Constructor & Destructor Documentation

MultiDimPolynomialGenerator()

StochasticTools::MultiDimPolynomialGenerator::MultiDimPolynomialGenerator ( )

inline

Definition at line 29 of file MultiDimPolynomialGenerator.h.

{}

~MultiDimPolynomialGenerator()

StochasticTools::MultiDimPolynomialGenerator::~MultiDimPolynomialGenerator ( )

default

Member Function Documentation

generateTuple()

std::vector< std::vector< unsigned int > > StochasticTools::MultiDimPolynomialGenerator::generateTuple ( unsigned int  n_dims, unsigned int  max_degree, bool  include_bias = true  )

static

Function computing for computing _tuple Example for ndim = 3, order = 4: | 0 | 1 0 0 | 2 1 1 0 0 0 | 3 2 2 1 1 1 0 0 0 0 | | 0 | 0 1 0 | 0 1 0 2 1 0 | 0 1 0 2 1 0 3 2 1 0 | | 0 | 0 0 1 | 0 0 1 0 1 2 | 0 0 1 0 1 2 0 1 2 3 |.

Definition at line 16 of file MultiDimPolynomialGenerator.C.

{
  // Compute full tensor tuple
  std::vector<std::vector<unsigned int>> tuple_1d(ndim);
  for (unsigned int d = 0; d < ndim; ++d)
  {
    tuple_1d[d].resize(order);
    for (unsigned int i = 0; i < order; ++i)
      tuple_1d[d][i] = i;
  }
 
  CartesianProduct<unsigned int> tensor_tuple(tuple_1d);
 
  // Remove polynomials that exceed the maximum order
  std::vector<std::vector<unsigned int>> tuple;
  for (unsigned int p = 0; p < tensor_tuple.numRows(); ++p)
  {
    std::vector<unsigned int> dorder = tensor_tuple.computeRow(p);
    unsigned int sum = std::accumulate(dorder.begin(), dorder.end(), 0);
    if (sum < order)
      tuple.push_back(dorder);
  }
 
  std::sort(tuple.begin(), tuple.end(), sortTuple);
 
  if (!include_bias)
    tuple.erase(tuple.begin()); // Erase intercept terms.
 
  return tuple;
}

sortTuple()

bool StochasticTools::MultiDimPolynomialGenerator::sortTuple ( const std::vector< unsigned int > &  first, const std::vector< unsigned int > &  second  )

static

Tuple sorter function.

Definition at line 50 of file MultiDimPolynomialGenerator.C.

{
  // Sort by sum
  if (std::accumulate(first.begin(), first.end(), 0) <
      std::accumulate(second.begin(), second.end(), 0))
    return true;
  else if (std::accumulate(first.begin(), first.end(), 0) >
           std::accumulate(second.begin(), second.end(), 0))
    return false;
 
  // Loop over elements
  for (unsigned int d = 0; d < first.size(); ++d)
  {
    if (first[d] == second[d])
      continue;
    return (first[d] > second[d]);
  }
 
  return false;
}

Referenced by generateTuple().

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The documentation for this class was generated from the following files:

• stochastic_tools/include/utils/MultiDimPolynomialGenerator.h
• stochastic_tools/src/utils/MultiDimPolynomialGenerator.C