Stokhos Package Browser (Single Doxygen Collection) Version of the Day
Loading...
Searching...
No Matches
random_field_example.cpp
Go to the documentation of this file.
1// @HEADER
2// ***********************************************************************
3//
4// Stokhos Package
5// Copyright (2009) Sandia Corporation
6//
7// Under terms of Contract DE-AC04-94AL85000, there is a non-exclusive
8// license for use of this work by or on behalf of the U.S. Government.
9//
10// Redistribution and use in source and binary forms, with or without
11// modification, are permitted provided that the following conditions are
12// met:
13//
14// 1. Redistributions of source code must retain the above copyright
15// notice, this list of conditions and the following disclaimer.
16//
17// 2. Redistributions in binary form must reproduce the above copyright
18// notice, this list of conditions and the following disclaimer in the
19// documentation and/or other materials provided with the distribution.
20//
21// 3. Neither the name of the Corporation nor the names of the
22// contributors may be used to endorse or promote products derived from
23// this software without specific prior written permission.
24//
25// THIS SOFTWARE IS PROVIDED BY SANDIA CORPORATION "AS IS" AND ANY
26// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL SANDIA CORPORATION OR THE
29// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
30// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
31// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
32// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
33// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
34// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
35// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36//
37// Questions? Contact Eric T. Phipps (etphipp@sandia.gov).
38//
39// ***********************************************************************
40// @HEADER
41
42// random_field_example
43//
44// usage:
45// random_field_example
46//
47// output:
48// prints out KL expansion for an exponential random field
49
50#include "Stokhos_ConfigDefs.h"
52
53// Functor for evaluating random field on the device
54template <typename Value, typename Device = Kokkos::DefaultExecutionSpace>
55struct RF {
56 typedef Value value_type;
57 typedef Device execution_space;
58
60 typedef Kokkos::View<value_type*,execution_space> point_type;
61 typedef Kokkos::View<value_type*,execution_space> rv_type;
62 typedef Kokkos::View<value_type*,execution_space> result_type;
63 const rf_type rf;
65 const rv_type rv;
67
68 RF(const rf_type& rf_, const point_type& x_, const rv_type& rv_) :
69 rf(rf_), x(x_), rv(rv_), y("y",1)
70 {
71 Kokkos::parallel_for(1, *this);
72 }
73
74 KOKKOS_INLINE_FUNCTION
75 void operator() (const unsigned i) const {
76 y(0) = rf.evaluate(x, rv);
77 }
78};
79
80int main(int argc, char **argv)
81{
82 Kokkos::initialize();
83
84 try {
85
86 // Create random field
87 int M = 10;
88 Teuchos::ParameterList solverParams;
89 solverParams.set("Number of KL Terms", M);
90 solverParams.set("Mean", 1.0);
91 solverParams.set("Standard Deviation", 0.1);
92 int ndim = 3;
93 Teuchos::Array<double> domain_upper(ndim), domain_lower(ndim),
94 correlation_length(ndim);
95 for (int i=0; i<ndim; i++) {
96 domain_upper[i] = 1.0;
97 domain_lower[i] = 0.0;
98 correlation_length[i] = 10.0;
99 }
100 solverParams.set("Domain Upper Bounds", domain_upper);
101 solverParams.set("Domain Lower Bounds", domain_lower);
102 solverParams.set("Correlation Lengths", correlation_length);
104 rf.print(std::cout);
105
106 // Evaluate random field at a point
107 Teuchos::Array<double> x(ndim);
108 for (int i=0; i<ndim; i++)
109 x[i] = (domain_upper[i] + domain_lower[i])/2.0 +
110 0.1*(domain_upper[i] - domain_lower[i])/2.0;
111 Teuchos::Array<double> rvar(M);
112 for (int i=0; i<M; i++)
113 rvar[i] = 1.5;
114 double result = rf.evaluate(x, rvar);
115 std::cout << "result (host) = " << result << std::endl;
116
117 // Evaluate random field in a functor on device
118 typedef Kokkos::View<double*> view_type;
119 typedef view_type::HostMirror host_view_type;
120 view_type x_view("x", ndim);
121 host_view_type host_x = Kokkos::create_mirror_view(x_view);
122 for (int i=0; i<ndim; i++)
123 host_x(i) = x[i];
124 Kokkos::deep_copy(x_view, host_x);
125 view_type rvar_view("rvar", M);
126 host_view_type host_rvar = Kokkos::create_mirror_view(rvar_view);
127 for (int i=0; i<M; i++)
128 host_rvar(i) = rvar[i];
129 Kokkos::deep_copy(rvar_view, host_rvar);
130 RF<double> rf_func(rf, x_view, rvar_view);
131 host_view_type host_y = Kokkos::create_mirror_view(rf_func.y);
132 Kokkos::deep_copy(host_y, rf_func.y);
133 double result2 = host_y(0);
134 std::cout << "result (device)= " << result2 << std::endl;
135 }
136 catch (std::exception& e) {
137 std::cout << e.what() << std::endl;
138 }
139
140 Kokkos::finalize();
141}
Class representing a KL expansion of an exponential random field.
KOKKOS_INLINE_FUNCTION Teuchos::PromotionTraits< typenamerv_type::value_type, value_type >::promote evaluate(const point_type &point, const rv_type &random_variables) const
Evaluate random field at a point.
void print(std::ostream &os) const
Print KL expansion.
void deep_copy(const Stokhos::CrsMatrix< ValueType, DstDevice, Layout > &dst, const Stokhos::CrsMatrix< ValueType, SrcDevice, Layout > &src)
Stokhos::CrsMatrix< ValueType, Device, Layout >::HostMirror create_mirror_view(const Stokhos::CrsMatrix< ValueType, Device, Layout > &A)
int main(int argc, char **argv)
RF(const rf_type &rf_, const point_type &x_, const rv_type &rv_)
Kokkos::View< value_type *, execution_space > rv_type
Device execution_space
const rf_type rf
const point_type x
const rv_type rv
Kokkos::View< value_type *, execution_space > result_type
KOKKOS_INLINE_FUNCTION void operator()(const unsigned i) const
Stokhos::KL::ExponentialRandomField< value_type, execution_space > rf_type
const result_type y
Kokkos::View< value_type *, execution_space > point_type