A modern, high-performance C++ header-only calculator library for evaluating mathematical expressions. Built with C++17/20 features, this library provides a robust and flexible expression parser that supports variables, functions, and comprehensive mathematical operations.
📖 Complete Documentation | 🚀 Quick Start Guide | 📋 API Reference
- 🚀 Header-only: Single file, easy integration
- 🔢 Multiple numeric types: Support for
int,float, anddouble - ⚡ High performance: Optimized expression parsing and evaluation
- 🧮 Comprehensive operations: Arithmetic, bitwise, and exponentiation
- 📐 Mathematical functions: Support for custom functions and variables
- 🛡️ Robust error handling: Detailed error messages with position information
- 📏 Operator precedence: Follows standard mathematical precedence rules
- 🔧 Template-based: Type-safe generic implementation
Simply download and include the header file:
curl -O https://raw.githubusercontent.com/ElementAstro/calculator/main/calculator.hpp#include "calculator.hpp"
#include <iostream>
int main() {
// Simple expression evaluation
double result = calculator::eval("3 + 4 * 2 / (1 - 5) ** 2");
std::cout << "Result: " << result << std::endl; // Output: 3.5
// Using variables and functions
calculator::ExpressionParser<double> parser;
parser.set("x", 5.0);
parser.set("square", [](double x) { return x * x; });
double advanced_result = parser.eval("square(x) + 10");
std::cout << "Advanced result: " << advanced_result << std::endl; // Output: 35
return 0;
}📖 See complete examples and tutorials →
| Category | Operators | Example | Types |
|---|---|---|---|
| Arithmetic | +, -, *, /, % |
3 + 4 * 2 |
All |
| Bitwise | |, ^, &, <<, >>, ~ |
5 & 3 |
int only |
| Exponentiation | **, e/E |
2 ** 3, 1.5e2 |
All |
| Unary | +, -, ~ |
+5, -3, ~7 |
All/int |
| Grouping | (, ) |
(2 + 3) * 4 |
All |
- Variables:
parser.set("x", 5.0)→"x + 10" - Functions:
parser.set("sqrt", [](double x) { return std::sqrt(x); })→"sqrt(16)" - Multiple Types:
int,float,doublewith type-specific behaviors - Error Handling: Detailed error messages with position information
📋 Complete operator reference and examples →
- Scientific Computing: Mathematical expression evaluation with variables and functions
- Configuration Systems: Dynamic formula parsing for application settings
- Game Development: Damage calculations, physics formulas, procedural generation
- Financial Applications: Interest calculations, custom metrics, business rules
- Educational Tools: Teaching mathematical concepts and expression evaluation
| Section | Description |
|---|---|
| Getting Started | Installation, quick start, and building |
| User Guide | Comprehensive usage instructions |
| API Reference | Complete class and function documentation |
| Examples | Practical code examples and patterns |
| Reference | Operators, types, and limitations |
- C++ Standard: C++17 minimum, C++20 recommended
- Compilers: GCC 8+, Clang 8+, MSVC 19+ (VS 2015+)
- Dependencies: None (header-only, standard library only)
- Platforms: Linux, Windows, macOS, FreeBSD
This project is licensed under the MIT License - see the LICENSE file for details.
We welcome contributions! Please see our Contributing Guide for details on how to get started.
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