https://github.com/leogtzr/math_evaluator_cpp

A tiny c++ math library for evaluate and recognize expressions.
https://github.com/leogtzr/math_evaluator_cpp

Last synced: 2 months ago
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A tiny c++ math library for evaluate and recognize expressions.

• Host: GitHub
• URL: https://github.com/leogtzr/math_evaluator_cpp
• Owner: leogtzr
• Created: 2013-12-17T05:46:10.000Z (over 10 years ago)
• Default Branch: master
• Last Pushed: 2014-01-17T19:27:54.000Z (over 10 years ago)
• Last Synced: 2024-01-23T16:59:33.759Z (5 months ago)
• Language: C
• Size: 746 KB
• Stars: 2
• Watchers: 3
• Forks: 3
• Open Issues: 0
• Metadata Files:
  • Readme: README.md

Lists

• awesome-android-cpp - leogtzr/math_evaluator_cpp - A tiny c++ math library for evaluate and recognize expressions. (TODO scan for Android support in followings)

README

        
A tiny c++ math library for evaluate and recognize expressions.

===============

Example:

--------------

    try {

        Parser evaluator;

        char expression[] = "1.0e0 + 2 * 3 - 123^2.0";

        evaluator.evaluate_expression_with_exception(expression);

        evaluator.parse(expression);

        double result = evaluator.get_numeric_answer();

        cout << "Ans: " << result << endl;

    } catch(ParsingException ex) {

        cout << "Error: " << ex.get_msg() << ", at " << ex.get_col() << endl;

    }

**Features:**

--------------

**Operators:**

    && ||

    == != < > <= >=

    + -

    * / %

    ^

    !

    Scientific notation

**Functions:**

    - factorial

    - log

    - acot

    - acosh

    - sign

    - acos

    - asech

    - atan

    - asinh

    - atanh

    - acoth

    - asin

    - acsc

    - acsch

    - asec

    - cot

    - coth

    - csc

    - csch

    - log10

    - log2

    - sec

    - sech

    - sqrt

    - tan

    - rand_0_to_1

    - sin

    - cos

**Numeric constants:**

    pi

    e

    g (gravity)

    random (random number)

**User defined variables:**

    char expression[] = "sin(pi + x)";        

    p.get_vars().add("x", 1.0);

    p.parse(expression);

    double result = p.get_numeric_answer();

**Recognition:**

    try {

        char expression[] = "pi^2.0 - sin(cos(tan(3.2e0)";

        p.evaluate_expression_with_exception(expression);

        cout << "Ok ... " << endl;

    } catch(ParsingException ex) {

        cout << "Error: " << ex.get_msg() << endl;

    }

**Evaluation:**

    try {

        char expression[] = "pi^2.0 - sin(cos(tan(3.2e0)))";

        p.evaluate_expression_with_exception(expression);

        p.parse(expression);

        double r = p.get_numeric_answer();

        cout << "Ok ... " << r << endl;

    } catch(ParsingException ex) {

        cout << "Error: " << ex.get_msg() << endl;

    }

**Arrays:**

    Parser p;

    p.get_arrays().create_array("a");

    

    for(int i = 1; i <= 10; i++) {

        p.get_arrays().add_element_to_array("a", (double)i);

    }

    try {

        char expression[] = "a[sin(pi) + 2]^3";

        p.parse(expression);

        double r = p.get_numeric_answer();

        cout << "Ok ... " << r << endl;

    } catch(ParsingException ex) {

        cout << "Error: " << ex.get_msg() << endl;

    }

**Tokenization:**

    try {

        char expression[] = "a[sin(pi) + 2]^3";

        Parser p;

        p.extract_tokens(expression);

        vector tokens = p.get_lexemas_positions();

        for(size_t i = 0; i < tokens.size(); i++) {

            cout << tokens[i] << endl;

        }

    } catch(ParsingException ex) {

        cout << "Error: " << ex.get_msg() << endl;

    }

Output:

    {a, init(0), tipo(OPERADOR)}

    {[, init(1), tipo(DELIMITADOR)}

    {sin, init(2), tipo(FUNCION)}

    {(, init(5), tipo(DELIMITADOR)}

    {pi, init(6), tipo(VARIABLE)}

    {), init(8), tipo(DELIMITADOR)}

    {+, init(10), tipo(DELIMITADOR)}

    {2, init(12), tipo(NUMERO)}

    {], init(13), tipo(DELIMITADOR)}

    {^, init(14), tipo(DELIMITADOR)}

    {3, init(15), tipo(NUMERO)}

**Function domain checking (trigonometric functions):**

    try {

        Parser p;

        char expression[] = "1 + asin(1.2)";

        p.evaluate_expression_with_exception(expression);

        p.parse(expression);

    } catch(ParsingException ex) {

        cout << "Error: " << ex.get_msg() << endl;

    }

Output:

    Error: out of domain for function '1.200000'