Line data Source code
1 0 : // Distributed under the MIT License.
2 : // See LICENSE.txt for details.
3 :
4 : #pragma once
5 :
6 : #include <algorithm>
7 : #include <cstddef>
8 : #include <memory>
9 : #include <optional>
10 : #include <string>
11 : #include <typeinfo>
12 : #include <unordered_map>
13 : #include <vector>
14 :
15 : #include "DataStructures/DataBox/DataBox.hpp"
16 : #include "Options/Auto.hpp"
17 : #include "Options/String.hpp"
18 : #include "Time/EvolutionOrdering.hpp"
19 : #include "Time/RequestsStepperErrorTolerances.hpp"
20 : #include "Time/StepChoosers/StepChooser.hpp"
21 : #include "Time/StepperErrorTolerances.hpp"
22 : #include "Time/TimeStepRequest.hpp"
23 : #include "Utilities/ErrorHandling/Assert.hpp"
24 : #include "Utilities/ErrorHandling/Error.hpp"
25 : #include "Utilities/Serialization/CharmPupable.hpp"
26 : #include "Utilities/StdHelpers.hpp"
27 : #include "Utilities/TMPL.hpp"
28 :
29 : /// \cond
30 : namespace PUP {
31 : class er;
32 : } // namespace PUP
33 : namespace Tags {
34 : struct FixedLtsRatio;
35 : struct TimeStep;
36 : } // namespace Tags
37 : namespace domain::Tags {
38 : template <size_t VolumeDim>
39 : struct Element;
40 : } // namespace domain::Tags
41 : namespace evolution::dg::Tags {
42 : template <size_t Dim>
43 : struct EqualRateRegions;
44 : } // namespace evolution::dg::Tags
45 : /// \endcond
46 :
47 0 : namespace evolution::dg::StepChoosers {
48 : /// Requests a slab size based on the desired step in regions with a
49 : /// fixed slab fraction.
50 : ///
51 : /// \note This StepChooser is not included in the
52 : /// `standard_step_choosers` list. Executables using the feature must
53 : /// include it explicitly in the `factory_creation` struct and add the
54 : /// `::Tags::FixedLtsRatio` tag to the element DataBox.
55 : template <size_t Dim>
56 1 : class FixedLtsRatio : public StepChooser<StepChooserUse::Slab>,
57 : public RequestsStepperErrorTolerances {
58 : public:
59 : /// \cond
60 : FixedLtsRatio() = default;
61 : explicit FixedLtsRatio(CkMigrateMessage* /*unused*/) {}
62 : using PUP::able::register_constructor;
63 : WRAPPED_PUPable_decl_template(FixedLtsRatio); // NOLINT
64 : /// \endcond
65 :
66 0 : struct StepChoosers {
67 0 : using type =
68 : std::vector<std::unique_ptr<::StepChooser<StepChooserUse::LtsStep>>>;
69 0 : static constexpr Options::String help{"LTS step choosers to test"};
70 : };
71 :
72 0 : struct Regions {
73 0 : using type =
74 : Options::Auto<std::vector<std::string>, Options::AutoLabel::All>;
75 0 : static constexpr Options::String help{"Regions to adjust based on"};
76 : };
77 :
78 0 : static constexpr Options::String help{
79 : "Requests a slab size based on the desired step in regions with a fixed "
80 : "slab fraction."};
81 0 : using options = tmpl::list<StepChoosers, Regions>;
82 :
83 0 : explicit FixedLtsRatio(
84 : std::vector<std::unique_ptr<::StepChooser<StepChooserUse::LtsStep>>>
85 : step_choosers,
86 : std::optional<std::vector<std::string>> regions);
87 :
88 0 : using argument_tags = tmpl::list<::Tags::DataBox>;
89 :
90 : template <typename DbTags>
91 0 : TimeStepRequest operator()(const db::DataBox<DbTags>& box,
92 : const double /*last_step*/) const {
93 : const auto& step_ratio = db::get<::Tags::FixedLtsRatio>(box);
94 : if (not step_ratio.has_value()) {
95 : return {};
96 : }
97 :
98 : if (regions_.has_value()) {
99 : const auto element_id = db::get<domain::Tags::Element<Dim>>(box).id();
100 : const auto& equal_rate_regions =
101 : db::get<Tags::EqualRateRegions<Dim>>(box);
102 : const auto& region_map = equal_rate_regions.regions();
103 : bool active = false;
104 : for (const auto& region_name : *regions_) {
105 : const auto region_it = region_map.find(region_name);
106 : if (region_it == region_map.end()) {
107 : ERROR_NO_TRACE("Unknown region name in FixedLtsRatio: "
108 : << region_name
109 : << ". Known regions: " << keys_of(region_map));
110 : }
111 : if (equal_rate_regions.is_in_region(region_it->second, element_id)) {
112 : active = true;
113 : // Don't break here so we check the remaining names for validity.
114 : }
115 : }
116 : if (not active) {
117 : return {};
118 : }
119 : }
120 :
121 : const auto& current_step = db::get<::Tags::TimeStep>(box);
122 : const evolution_less<double> less{current_step.is_positive()};
123 :
124 : std::optional<double> size_goal{};
125 : std::optional<double> size{};
126 : for (const auto& step_chooser : step_choosers_) {
127 : const auto step_request =
128 : step_chooser->desired_step(current_step.value(), box);
129 :
130 : if (step_request.size_goal.has_value()) {
131 : if (size_goal.has_value()) {
132 : *size_goal = std::min(*size_goal, *step_request.size_goal, less);
133 : } else {
134 : size_goal = step_request.size_goal;
135 : }
136 : }
137 : if (step_request.size.has_value()) {
138 : if (size.has_value()) {
139 : *size = std::min(*size, *step_request.size, less);
140 : } else {
141 : size = step_request.size;
142 : }
143 : }
144 :
145 : // As of writing (Oct. 2024), no StepChooserUse::LtsStep chooser
146 : // sets these.
147 : ASSERT(not(step_request.end.has_value() or
148 : step_request.size_hard_limit.has_value() or
149 : step_request.end_hard_limit.has_value()),
150 : "Unhandled field set by StepChooser. Please file a bug "
151 : "containing the options passed to FixedLtsRatio.");
152 : }
153 :
154 : if (size_goal.has_value()) {
155 : *size_goal *= *step_ratio;
156 : }
157 : if (size.has_value()) {
158 : *size *= *step_ratio;
159 : if (size_goal.has_value() and less(*size_goal, *size)) {
160 : // Not allowed to request a goal and a bigger step.
161 : size.reset();
162 : }
163 : }
164 :
165 : return {.size_goal = size_goal, .size = size};
166 : }
167 :
168 1 : bool uses_local_data() const override;
169 1 : bool can_be_delayed() const override;
170 1 : bool must_set_step_size() const override;
171 :
172 1 : std::unordered_map<std::type_index, StepperErrorTolerances> tolerances()
173 : const override;
174 :
175 0 : void pup(PUP::er& p) override;
176 :
177 : private:
178 : std::vector<std::unique_ptr<::StepChooser<StepChooserUse::LtsStep>>>
179 0 : step_choosers_;
180 0 : std::optional<std::vector<std::string>> regions_;
181 : };
182 : } // namespace evolution::dg::StepChoosers
|
