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
|
/*
**************************************************************
* C++ Mathematical Expression Toolkit Library *
* *
* Simple Example 19 *
* Author: Arash Partow (1999-2024) *
* 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 *
* SPDX-License-Identifier: MIT *
* *
**************************************************************
*/
#include <cstdio>
#include <cstdlib>
#include <ctime>
#include <string>
#include "exprtk.hpp"
template <typename T>
class randu : public exprtk::igeneric_function<T>
{
public:
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::vector_view vector_t;
using exprtk::igeneric_function<T>::operator();
randu()
: exprtk::igeneric_function<T>("V|VTT")
/*
Overloads:
0. V - vector
1. VTT - vector, r0, r1
*/
{ ::srand(static_cast<unsigned int>(time(NULL))); }
inline T operator()(const std::size_t& ps_index, parameter_list_t parameters)
{
vector_t v(parameters[0]);
std::size_t r0 = 0;
std::size_t r1 = v.size() - 1;
using namespace exprtk::rtl::vecops::helper;
if (
(1 == ps_index) &&
!load_vector_range<T>::process(parameters, r0, r1, 1, 2, 0)
)
return T(0);
for (std::size_t i = r0; i <= r1; ++i)
{
v[i] = rnd();
}
return T(1);
}
private:
inline T rnd()
{
// Note: Do not use this in production
// Result is in the interval [0,1)
return T(::rand() / T(RAND_MAX + 1.0));
}
};
template <typename T>
void vector_randu()
{
typedef exprtk::symbol_table<T> symbol_table_t;
typedef exprtk::expression<T> expression_t;
typedef exprtk::parser<T> parser_t;
const std::string vecrandu_program =
" var noise[6] := [0]; "
" "
" if (randu(noise,0,5) == false) "
" { "
" println('Failed to generate noise'); "
" return [false]; "
" }; "
" "
" var noisy[noise[]] := signal + (noise - 1/2); "
" "
" for (var i := 0; i < noisy[]; i += 1) "
" { "
" println('noisy[',i,'] = ', noisy[i]); "
" }; "
" "
" println('avg: ', avg(noisy)); "
" ";
T signal[] = { T(1.1), T(2.2), T(3.3), T(4.4), T(5.5), T(6.6), T(7.7) };
exprtk::rtl::io::println<T> println;
randu<T> randu;
symbol_table_t symbol_table;
symbol_table.add_vector ("signal" , signal );
symbol_table.add_function("println", println);
symbol_table.add_function("randu" , randu );
expression_t expression;
expression.register_symbol_table(symbol_table);
parser_t parser;
parser.compile(vecrandu_program,expression);
expression.value();
}
int main()
{
vector_randu<double>();
return 0;
}
|