/[escript]/trunk/escript/src/DataLazy.h
ViewVC logotype

Contents of /trunk/escript/src/DataLazy.h

Parent Directory Parent Directory | Revision Log Revision Log


Revision 1903 - (show annotations)
Wed Oct 22 06:11:01 2008 UTC (11 years, 5 months ago) by jfenwick
Original Path: branches/schroedinger/escript/src/DataLazy.h
File MIME type: text/plain
File size: 6819 byte(s)
More fixes to doxygen for scons.
Added += and other forms of +

1
2 /*******************************************************
3 *
4 * Copyright (c) 2003-2008 by University of Queensland
5 * Earth Systems Science Computational Center (ESSCC)
6 * http://www.uq.edu.au/esscc
7 *
8 * Primary Business: Queensland, Australia
9 * Licensed under the Open Software License version 3.0
10 * http://www.opensource.org/licenses/osl-3.0.php
11 *
12 *******************************************************/
13
14
15 #if !defined escript_DataLazy_20081008_H
16 #define escript_DataLazy_20081008_H
17 #include "system_dep.h"
18
19 #include "DataAbstract.h"
20
21 #include <string>
22 #include <functional>
23
24 #include "LocalOps.h" // for tensor_binary_op
25
26 namespace escript {
27
28 enum ES_optype
29 {
30 UNKNOWNOP=0,
31 IDENTITY=1,
32 ADD=2,
33 SUB=3,
34 MUL=4,
35 DIV=5,
36 SIN=6,
37 COS=7,
38 TAN=8,
39 ASIN=9,
40 ACOS=10,
41 ATAN=11,
42 SINH=12,
43 COSH=13,
44 TANH=14,
45 ERF=15,
46 ASINH=16,
47 ACOSH=17,
48 ATANH=18,
49 LOG10=19,
50 LOG=20,
51 SIGN=21,
52 ABS=22,
53 NEG=23,
54 POS=24,
55 EXP=25,
56 SQRT=26,
57 RECIP=27,
58 GZ=28,
59 LZ=29,
60 GEZ=30,
61 LEZ=31
62 };
63
64 const std::string&
65 opToString(ES_optype op);
66
67 /**
68 \class escript::DataLazy
69 \brief Wraps an expression tree of other DataObjects.
70 The data will be evaluated when required.
71
72
73 NOTE: This class assumes that the Data being pointed at are immutable.
74 */
75
76 class DataLazy;
77
78 typedef POINTER_WRAPPER_CLASS(DataLazy) DataLazy_ptr;
79 typedef POINTER_WRAPPER_CLASS(const DataLazy) const_DataLazy_ptr;
80
81 class DataLazy : public DataAbstract
82 {
83
84 typedef DataAbstract parent;
85 typedef DataTypes::ValueType ValueType;
86 typedef DataTypes::ShapeType ShapeType;
87
88 public:
89 /**
90 \brief Create an IDENTITY DataLazy for the given DataAbstract.
91 \param p DataAbstract to be wrapped.
92 \throws DataException if p is lazy data or it is not constant, tagged or expanded.
93 */
94 ESCRIPT_DLL_API
95 DataLazy(DataAbstract_ptr p);
96
97
98 /**
99 \brief Produce a DataLazy for a unary operation.
100 \param left DataAbstract to be operated on.
101 \param op unary operation to perform.
102 \throws DataException if op is not a unary operation or if p cannot be converted to a DataLazy.
103 Note that IDENTITY is not considered a unary operation.
104 */
105 ESCRIPT_DLL_API
106 DataLazy(DataAbstract_ptr left, ES_optype op);
107
108 /**
109 \brief Produce a DataLazy for a binary operation.
110 \param left left operand
111 \param right right operand
112 \param op unary operation to perform.
113 \throws DataException if op is not a binary operation or if left or right cannot be converted to a DataLazy.
114 */
115 ESCRIPT_DLL_API
116 DataLazy(DataAbstract_ptr left, DataAbstract_ptr right, ES_optype op);
117
118 ESCRIPT_DLL_API
119 ~DataLazy();
120
121 /**
122 \brief Evaluate the lazy expression.
123 \return A DataReady with the value of the lazy expresion.
124 */
125 ESCRIPT_DLL_API
126 DataReady_ptr
127 resolve();
128
129 ESCRIPT_DLL_API
130 std::string
131 toString() const;
132
133 ESCRIPT_DLL_API
134 DataAbstract*
135 deepCopy();
136
137
138 /**
139 \brief
140 Return the number of doubles that would be stored for this Data object if it were resolved.
141 */
142 ESCRIPT_DLL_API
143 ValueType::size_type
144 getLength() const;
145
146
147 ESCRIPT_DLL_API
148 DataAbstract*
149 getSlice(const DataTypes::RegionType& region) const;
150
151
152 DataTypes::ValueType::size_type
153 getPointOffset(int sampleNo,
154 int dataPointNo) const;
155
156
157 /**
158 \return the number of samples which need to be stored to evaluate the expression.
159 */
160 ESCRIPT_DLL_API
161 int
162 getBuffsRequired() const;
163
164 /**
165 \brief Produces an IDENTITY DataLazy containing zero.
166 The result will have the same shape and functionspace as before.
167 */
168 ESCRIPT_DLL_API
169 virtual void
170 setToZero();
171
172 private:
173 DataReady_ptr m_id; // For IDENTITY nodes, stores a wrapped value.
174 DataLazy_ptr m_left, m_right; // operands for operation.
175 ES_optype m_op; // operation to perform.
176 size_t m_length; // number of values represented by the operation
177
178 int m_buffsRequired; // how many samples are required to evaluate this expression
179 size_t m_samplesize; // number of values required to store a sample
180
181 char m_readytype; // E for expanded, T for tagged, C for constant
182
183
184 /**
185 Does the work for toString.
186 */
187 void
188 intoString(std::ostringstream& oss) const;
189
190 /**
191 \brief Converts the DataLazy into an IDENTITY storing the value of the expression.
192 This method uses the original methods on the Data class to evaluate the expressions.
193 For this reason, it should not be used on DataExpanded instances. (To do so would defeat
194 the purpose of using DataLazy in the first place).
195 */
196 void
197 collapse(); // converts the node into an IDENTITY node
198
199
200 /**
201 \brief Evaluates the expression using methods on Data.
202 This does the work for the collapse method.
203 For reasons of efficiency do not call this method on DataExpanded nodes.
204 */
205 DataReady_ptr
206 collapseToReady();
207
208 /**
209 \brief Compute the value of the expression for the given sample.
210 \return Vector which stores the value of the subexpression for the given sample.
211 \param v A vector to store intermediate results.
212 \param offset Index in v to begin storing results.
213 \param sampleNo Sample number to evaluate.
214 \param roffset (output parameter) the offset in the return vector where the result begins.
215
216 The return value will be an existing vector so do not deallocate it.
217 */
218 const ValueType*
219 resolveSample(ValueType& v, size_t offset ,int sampleNo, size_t& roffset);
220
221 /**
222 \brief Compute the value of the expression (binary operation) for the given sample.
223 \return Vector which stores the value of the subexpression for the given sample.
224 \param v A vector to store intermediate results.
225 \param offset Index in v to begin storing results.
226 \param sampleNo Sample number to evaluate.
227 \param roffset (output parameter) the offset in the return vector where the result begins.
228
229 The return value will be an existing vector so do not deallocate it.
230 If the result is stored in v it should be stored at the offset given.
231 Everything from offset to the end of v should be considered available for this method to use.
232 */
233 ValueType*
234 resolveUnary(ValueType& v, size_t offset,int sampleNo, size_t& roffset) const;
235
236 /**
237 \brief Compute the value of the expression (binary operation) for the given sample.
238 \return Vector which stores the value of the subexpression for the given sample.
239 \param v A vector to store intermediate results.
240 \param offset Index in v to begin storing results.
241 \param sampleNo Sample number to evaluate.
242 \param roffset (output parameter) the offset in the return vector where the result begins.
243
244 The return value will be an existing vector so do not deallocate it.
245 If the result is stored in v it should be stored at the offset given.
246 Everything from offset to the end of v should be considered available for this method to use.
247 */
248 ValueType*
249 resolveBinary(ValueType& v, size_t offset,int sampleNo, size_t& roffset) const;
250
251 };
252
253 }
254 #endif

  ViewVC Help
Powered by ViewVC 1.1.26