-
Notifications
You must be signed in to change notification settings - Fork 11
/
exprtk_vectornorm.cpp
195 lines (160 loc) · 5.88 KB
/
exprtk_vectornorm.cpp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
/*
**************************************************************
* C++ Mathematical Expression Toolkit Library *
* *
* ExprTk L-Norm Of A Vector *
* Author: Arash Partow (1999-2023) *
* URL: https://www.partow.net/programming/exprtk/index.html *
* *
* Copyright notice: *
* Free use of the Mathematical Expression Toolkit Library is *
* permitted under the guidelines and in accordance with the *
* most current version of the MIT License. *
* https://www.opensource.org/licenses/MIT *
* *
**************************************************************
*/
#include <cmath>
#include <cstdio>
#include <iostream>
#include <string>
#include <vector>
#include "exprtk.hpp"
template <typename T>
struct norm : public exprtk::igeneric_function<T>
{
typedef typename exprtk::igeneric_function<T> igfun_t;
typedef typename igfun_t::parameter_list_t parameter_list_t;
typedef typename igfun_t::generic_type generic_type;
typedef typename generic_type::scalar_view scalar_t;
typedef typename generic_type::vector_view vector_t;
using exprtk::igeneric_function<T>::operator();
norm()
: exprtk::igeneric_function<T>("V|VTT|VT|VTTT")
/*
Overloads:
0. V - vector
1. VTT - vector, r0, r1
2. VT - vector, l-power
3. VTTT - vector, l-power, r0, r1
*/
{}
inline T operator()(const std::size_t& ps_index, parameter_list_t parameters)
{
unsigned int l = 2;
// Determine the l-power
if (
(2 == ps_index) ||
(3 == ps_index)
)
{
if (!scalar_t(parameters[1]).to_uint(l))
return std::numeric_limits<T>::quiet_NaN();
}
const vector_t vec(parameters[0]);
std::size_t r0 = 0;
std::size_t r1 = vec.size() - 1;
// Determine the range over the vector
if (
(1 == ps_index) ||
(3 == ps_index)
)
{
if (!scalar_t(parameters[(1 == ps_index) ? 1 : 2]).to_uint(r0))
return std::numeric_limits<T>::quiet_NaN();
if (!scalar_t(parameters[(1 == ps_index) ? 2 : 3]).to_uint(r1))
return std::numeric_limits<T>::quiet_NaN();
}
switch (l)
{
#define norm_def(N) case N : return norm_impl<N>(vec,r0,r1);
norm_def( 1) norm_def( 2) norm_def( 3) norm_def( 4)
norm_def( 5) norm_def( 6) norm_def( 7) norm_def( 8)
norm_def( 9) norm_def(10) norm_def(11) norm_def(12)
norm_def(13) norm_def(14) norm_def(15) norm_def(16)
norm_def(17) norm_def(18) norm_def(19) norm_def(20)
norm_def(21) norm_def(22) norm_def(23) norm_def(24)
norm_def(25) norm_def(26) norm_def(27) norm_def(28)
norm_def(29) norm_def(30) norm_def(31) norm_def(32)
default : return norm_impl(vec,l,r0,r1);
}
}
template <unsigned int Pow>
inline T norm_impl(const vector_t& vector, const std::size_t r0, const std::size_t r1)
{
T sum = T(0);
for (std::size_t i = r0; i <= r1; ++i)
{
sum += exprtk::details::numeric::fast_exp<T,Pow>::result(std::abs(vector[i]));
}
switch (Pow)
{
case 1 : return sum;
case 2 : return exprtk::details::numeric::sqrt(sum);
default : return exprtk::details::numeric::pow(sum, T(1) / Pow);
}
}
inline T norm_impl(const vector_t& vector, unsigned int pow, const std::size_t r0, const std::size_t r1)
{
T sum = T(0);
for (std::size_t i = r0; i <= r1; ++i)
{
sum += exprtk::details::numeric::pow(std::abs(vector[i]),T(pow));
}
return exprtk::details::numeric::pow(sum,T(1) / pow);
}
};
template <typename T>
void norm_of_vector()
{
typedef exprtk::symbol_table<T> symbol_table_t;
typedef exprtk::expression<T> expression_t;
typedef exprtk::parser<T> parser_t;
symbol_table_t symbol_table;
T x[] = { T(1), T(2), T(3), T(4), T(5) };
std::vector<T> y;
y.push_back(T(5)); y.push_back(T(6));
y.push_back(T(7)); y.push_back(T(8));
y.push_back(T(9)); y.push_back(T(0));
symbol_table.add_vector("x", x);
symbol_table.add_vector("y", y);
norm<T> norm_;
symbol_table.add_function("norm",norm_);
const std::string vector_norm_program[] =
{
" norm(x) ",
" norm(x,1) ",
" norm(x,2) ",
" norm(x,3) ",
" norm(x,4) ",
" norm(x,5) ",
" norm(2x+1) ",
" norm(2x+1,1) ",
" norm(2x+1,2) ",
" norm(2x+1,3) ",
" norm(2x+1,4) ",
" norm(2x+1,5) ",
" norm(2x+y/3-4) ",
" norm(2x+y/3-4,1) ",
" norm(2x+y/3-4,2) ",
" norm(2x+y/3-4,3) ",
" norm(2x+y/3-4,4) ",
" norm(2x+y/3-4,5) "
};
const std::size_t vecnorm_program_size = sizeof(vector_norm_program) / sizeof(std::string);
parser_t parser;
for (std::size_t i = 0; i < vecnorm_program_size; ++i)
{
expression_t expression;
expression.register_symbol_table(symbol_table);
parser.compile(vector_norm_program[i], expression);
printf("%s = %15.8f\n",
vector_norm_program[i].c_str(),
expression.value());
}
}
int main()
{
norm_of_vector<double>();
return 0;
}