🧮 Equations-Parser (muParserX)

A powerful C++ mathematical expression parser library with support for complex numbers, matrices, strings, date/time operations, and 60+ built-in functions. Originally based on muParserX by Ingo Berg, this library provides comprehensive mathematical expression evaluation capabilities.

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🚀 Key Features

• ✅ 60+ Built-in Functions - Comprehensive mathematical function library
• ✅ Multiple Data Types - Numbers, Complex, Strings, Matrices, Arrays
• ✅ Advanced Operations - Trigonometry, Logarithms, Date/Time, String manipulation
• ✅ WebAssembly Ready - Compile to WASM for web applications
• ✅ Thread Safe - Safe for multi-threaded applications
• ✅ Extensible - Easy to add custom functions and operators
• ✅ C++11 Compatible - Modern C++ features

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📚 Complete Function Reference

➕ Arithmetic Operations

Operation	Syntax	Description	Example
Addition	a + b	Basic addition	2 + 3 = 5
Subtraction	a - b	Basic subtraction	5 - 2 = 3
Multiplication	a * b	Basic multiplication	4 * 7 = 28
Division	a / b	Basic division	8 / 2 = 4
Power	a ^ b	Exponentiation	2 ^ 3 = 8
Modulo	a % b	Remainder operation	7 % 3 = 1
Assignment	a = b	Variable assignment	x = 10
Compound Assignment	+=, -=, *=, /=	In-place operations	x += 5

📐 Trigonometric Functions

Function	Syntax	Description	Domain	Example
Sine	sin(x)	Sine function	All reals	sin(π/2) = 1
Cosine	cos(x)	Cosine function	All reals	cos(0) = 1
Tangent	tan(x)	Tangent function	x ≠ π/2 + nπ	tan(π/4) = 1
Arc Sine	asin(x)	Inverse sine	[-1, 1]	asin(0.5) = π/6
Arc Cosine	acos(x)	Inverse cosine	[-1, 1]	acos(0.5) = π/3
Arc Tangent	atan(x)	Inverse tangent	All reals	atan(1) = π/4
Arc Tangent 2	atan2(y,x)	Two-argument arctangent	All reals	atan2(1,1) = π/4

〰️ Hyperbolic Functions

Function	Syntax	Description	Example
Hyperbolic Sine	sinh(x)	Hyperbolic sine	sinh(1) = 1.175
Hyperbolic Cosine	cosh(x)	Hyperbolic cosine	cosh(0) = 1
Hyperbolic Tangent	tanh(x)	Hyperbolic tangent	tanh(1) = 0.762
Inverse Hyperbolic Sine	asinh(x)	Inverse hyperbolic sine	asinh(1) = 0.881
Inverse Hyperbolic Cosine	acosh(x)	Inverse hyperbolic cosine	acosh(1.5) = 0.962
Inverse Hyperbolic Tangent	atanh(x)	Inverse hyperbolic tangent	atanh(0.5) = 0.549

📊 Logarithmic & Exponential Functions

Function	Syntax	Description	Domain	Example
Natural Logarithm	ln(x), log(x)	Base-e logarithm	x > 0	ln(e) = 1
Common Logarithm	log10(x)	Base-10 logarithm	x > 0	log10(100) = 2
Binary Logarithm	log2(x)	Base-2 logarithm	x > 0	log2(8) = 3
Exponential	exp(x)	e raised to x	All reals	exp(1) = e

🧮 Mathematical Functions

Function	Syntax	Description	Example
Absolute Value	abs(x)	Absolute value	abs(-5) = 5
Square Root	sqrt(x)	Square root	sqrt(16) = 4
Cube Root	cbrt(x)	Cube root	cbrt(27) = 3
Power	pow(x,y)	x raised to y	pow(2,3) = 8
Hypotenuse	hypot(x,y)	√(x² + y²)	hypot(3,4) = 5
Round	round(x)	Round to nearest integer	round(3.7) = 4
Round Decimal	round_decimal(x,n)	Round to n decimals	round_decimal(3.14159,2) = 3.14
Remainder	fmod(x,y)	Floating-point remainder	fmod(7,3) = 1
IEEE Remainder	remainder(x,y)	IEEE remainder	remainder(7,3) = 1

📝 String Functions

Function	Syntax	Description	Example
Concatenate	concat(s1,s2)	Join two strings	concat("Hello"," World") = "Hello World"
Length	length(s)	String length	length("test") = 4
To Uppercase	toupper(s)	Convert to uppercase	toupper("hello") = "HELLO"
To Lowercase	tolower(s)	Convert to lowercase	tolower("WORLD") = "world"
Left Substring	left(s,n)	Get leftmost n chars	left("Hello",3) = "Hel"
Right Substring	right(s,n)	Get rightmost n chars	right("World",3) = "rld"
String to Number	str2number(s)	Parse string as number	str2number("123.45") = 123.45
Number to String	string(x)	Convert to string	string(123) = "123"
Type Conversion	number(x)	Convert to number	number("42") = 42
Contains	contains(s1,s2)	Check if s1 contains s2	contains("Hello","ell") = true
HTML Link	link(text,url)	Create HTML link	link("Google","http://google.com")
Default Value	default_value(val,def)	Return default if null	default_value(null,"empty") = "empty"
Calculate	calculate(s)	Evaluate expression string	calculate("2+2") = 4

🔢 Matrix Functions

Function	Syntax	Description	Example
Ones Matrix	ones(rows,cols)	Matrix filled with ones	ones(2,3) = [[1,1,1],[1,1,1]]
Zeros Matrix	zeros(rows,cols)	Matrix filled with zeros	zeros(2,2) = [[0,0],[0,0]]
Identity Matrix	eye(n)	n×n identity matrix	eye(2) = [[1,0],[0,1]]
Matrix Size	size(matrix)	Get matrix dimensions	size([[1,2],[3,4]]) = [2,2]
Transpose	matrix'	Matrix transpose	[[1,2],[3,4]]' = [[1,3],[2,4]]

📊 Array Functions

Function	Syntax	Description	Example
Size Of	sizeof(array)	Number of elements	sizeof([1,2,3,4]) = 4

📅 Date Functions

Function	Syntax	Description	Format	Example
Current Date	current_date()	Today's date	YYYY-MM-DD	current_date() = "2023-12-01"
Days Difference	daysdiff(d1,d2)	Days between dates	YYYY-MM-DD	daysdiff("2023-12-01","2023-12-10") = 9
Hours Difference	hoursdiff(dt1,dt2)	Hours between datetimes	YYYY-MM-DDTHH:MM	hoursdiff("2023-12-01T10:00","2023-12-01T15:30") = 5.5
Add Days	add_days(date,n)	Add n days to date	YYYY-MM-DD	add_days("2023-12-01",7) = "2023-12-08"
Week of Year	weekyear(date)	ISO week number	YYYY-MM-DD	weekyear("2023-12-01") = 48
Week Day	weekday(date)	Day of week (0=Sunday)	YYYY-MM-DD	weekday("2023-12-01") = 5
Week Day Localized	weekday(date,locale)	Localized day name	Multiple locales	weekday("2023-12-01","en") = "Friday"

🕐 Time Functions

Function	Syntax	Description	Format	Example
Current Time	current_time()	Current time	HH:MM:SS	current_time() = "14:30:15"
Current Time Offset	current_time(offset)	Time with GMT offset	HH:MM:SS	current_time(-5) = "09:30:15"
Time Difference	timediff(t1,t2)	Hours between times	HH:MM:SS	timediff("10:00:00","15:30:00") = 5.5

🛠️ Utility Functions

Function	Syntax	Description	Example
Mask	mask(pattern,number)	Apply formatting mask	mask("000-000",123456) = "123-456"
Regex	regex(text,pattern)	Regex pattern matching	regex("Hello123","[0-9]+") = "123"
Parser ID	parserid()	Parser version info	parserid() = "muParserX V4.0.7"

⚖️ Comparison & Logical Operators

Operator	Syntax	Description	Example
Greater Than	a > b	Comparison	5 > 3 = true
Less Than	a < b	Comparison	2 < 7 = true
Greater or Equal	a >= b	Comparison	5 >= 5 = true
Less or Equal	a <= b	Comparison	3 <= 4 = true
Equal	a == b	Equality	3 == 3 = true
Not Equal	a != b	Inequality	3 != 4 = true
Logical AND	a && b, a and b	Logical conjunction	true && false = false
Logical OR	a || b, a or b	Logical disjunction	true || false = true
Bitwise AND	a & b	Bitwise conjunction	5 & 3 = 1
Bitwise OR	a | b	Bitwise disjunction	5 | 3 = 7
Left Shift	a << b	Bitwise left shift	1 << 3 = 8
Right Shift	a >> b	Bitwise right shift	8 >> 3 = 1

❓ Conditional Expressions

Expression	Syntax	Description	Example
Ternary Operator	condition ? true_val : false_val	Conditional expression	5 > 3 ? "yes" : "no" = "yes"

🔢 Mathematical Constants

Constant	Value	Description
pi	3.141592653589793...	Pi (π)
e	2.718281828459045...	Euler's number (e)
null	NULL	Null value

📈 Aggregation Functions

Function	Syntax	Description	Example
Minimum	min(x1,x2,...)	Smallest value	min(1,5,2,8) = 1
Maximum	max(x1,x2,...)	Largest value	max(1,5,2,8) = 8
Sum	sum(x1,x2,...)	Sum of all values	sum(1,2,3,4) = 10
Average	avg(x1,x2,...)	Average of all values	avg(1,2,3,4) = 2.5

🔄 Type Casting

Operator	Syntax	Description	Example
Cast to Float	(float)x	Convert to floating point	(float)5 = 5.0
Cast to Integer	(int)x	Convert to integer	(int)3.7 = 3
Factorial	x!	Factorial (postfix)	5! = 120

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🏗️ Architecture Overview

graph TB
    subgraph "Expression Parser Architecture"
        A[Expression String] --> B[Tokenizer]
        B --> C[RPN Converter]
        C --> D[Expression Tree]
        D --> E[Evaluator]
        E --> F[Result Value]

        subgraph "Package System"
            G[Common Package]
            H[Math Package]
            I[String Package]
            J[Matrix Package]
            K[Date/Time Package]
        end

        D --> G
        D --> H
        D --> I
        D --> J
        D --> K
    end

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🎯 Expression Examples

Basic Mathematics

// Arithmetic operations
"2 + 3 * 4"                    // Result: 14
"(5 + 3) / 2"                  // Result: 4
"2 ^ 3"                        // Result: 8

// Mathematical functions
"sqrt(16)"                     // Result: 4
"sin(pi/2)"                    // Result: 1
"log10(100)"                   // Result: 2
"abs(-5)"                      // Result: 5

String Operations

// String manipulation
"concat('Hello', ' World')"     // Result: "Hello World"
"toupper('hello')"             // Result: "HELLO"
"length('test')"               // Result: 4
"contains('Hello World', 'World')" // Result: true

Date & Time Operations

// Date calculations
"current_date()"                              // Result: "2023-12-01"
"daysdiff('2023-12-01', '2023-12-10')"       // Result: 9
"add_days('2023-12-01', 7)"                  // Result: "2023-12-08"
"weekday('2023-12-01')"                      // Result: 5 (Friday)

// Time calculations
"current_time()"                             // Result: "14:30:15"
"timediff('10:00:00', '15:30:00')"          // Result: 5.5

Matrix Operations

// Matrix creation and manipulation
"ones(2, 3)"                   // Result: [[1,1,1],[1,1,1]]
"zeros(2, 2)"                  // Result: [[0,0],[0,0]]
"eye(3)"                       // Result: [[1,0,0],[0,1,0],[0,0,1]]

Conditional Logic

// Ternary operations
"5 > 3 ? 'yes' : 'no'"         // Result: "yes"
"x = 10; x > 5 ? x * 2 : x / 2" // Result: 20

Complex Expressions

// Multi-line expressions
"""
x = 5
y = 3
result = x > y ? sqrt(x^2 + y^2) : abs(x - y)
result
"""                            // Result: 5.831 (hypotenuse)

// Nested function calls
"round_decimal(sin(pi/4) * 100, 2)"  // Result: 70.71

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📊 Supported Data Types

graph LR
    subgraph "Value System"
        A[Value Type] --> B[Float]
        A --> C[Integer]
        A --> D[Complex]
        A --> E[String]
        A --> F[Boolean]
        A --> G[Matrix]
        A --> H[Array]
    end

    B --> I[Mathematical Operations]
    C --> I
    D --> J[Complex Mathematics]
    E --> K[String Operations]
    F --> L[Logical Operations]
    G --> M[Matrix Operations]
    H --> N[Array Operations]

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🚀 Integration Examples

C++ Usage

#include "equationsParser.h"

// Basic evaluation
std::string result = EquationsParser::Calc("sin(pi/2)");
// result = "1"

// JSON response with type information
std::string jsonResult = EquationsParser::CalcJson("sqrt(16)");
// jsonResult = {"val":"4","type":"f"}

WebAssembly Integration

// JavaScript wrapper usage
const parser = new EquationsParserWrapper();
await parser.initialize();

const result = parser.evaluateEquation("2 + 3 * 4");
console.log(result);
// { value: "14", type: "i", success: true }

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🏷️ Version History

Version	Date	Key Changes
4.0.7	2016-03-31	Added atan2, remainder, fmod functions, bug fixes
4.0.5	2015-11-20	New functions: cbrt, hypot, pow for complex numbers
4.0.0	2015-06-22	Major API changes, removed integer constructors
3.0.0	2014-05-25	C++11 required, array construction {1,2,3}, matrix functions
2.1.0	2011-10-16	Matrix data type, multidimensional index operator

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📜 License

This library is distributed under the BSD-2-Clause License ("Simplified" or "FreeBSD" License).

Copyright (C) 2016, Ingo Berg
All rights reserved.

Redistribution and use in source and binary forms, with or without 
modification, are permitted provided that the following conditions are met:

* Redistributions of source code must retain the above copyright notice, 
  this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright notice, 
  this list of conditions and the following disclaimer in the documentation 
  and/or other materials provided with the distribution.

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👥 Contributors

• Ingo Berg - Original author and maintainer
• Martin Rotter - Core contributor
• Josh Blum - Core contributor
• Community - Various bug fixes and improvements

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🔗 Links

• Original Project: muParserX
• Documentation: Full API Documentation
• Examples: Sample Code
• Issues: Report bugs and request features

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🎉 Quick Start

1. Include the library

#include "equationsParser.h"

2. Evaluate expressions

std::string result = EquationsParser::Calc("sin(pi/2) + cos(0)");
// result = "2"

3. Get detailed results

std::string json = EquationsParser::CalcJson("sqrt(16)");
// json = {"val":"4","type":"f"}

Ready to parse complex mathematical expressions with ease! 🚀