/*

**************************************************************

* C++ Mathematical Expression Toolkit Library *

* *

* Simple Example 01 *

* Author: Arash Partow (1999-2025) *

* 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 <string>

#include "exprtk.hpp"

template <typename T>

void trig_function()

{

typedef exprtk::symbol_table<T> symbol_table_t;

typedef exprtk::expression<T> expression_t;

typedef exprtk::parser<T> parser_t;

const std::string expression_string =

"clamp(-1.0, sin(2 * pi * x) + cos(x / 2 * pi), +1.0)";

T x;

symbol_table_t symbol_table;

symbol_table.add_variable("x",x);

symbol_table.add_constants();

expression_t expression;

expression.register_symbol_table(symbol_table);

parser_t parser;

parser.compile(expression_string,expression);

for (x = T(-5); x <= T(+5); x += T(0.001))

{

const T y = expression.value();

printf("%19.15f\t%19.15f\n", x, y);

}

}

int main()

{

trig_function<double>();

return 0;

}