EquationParser Class Reference

Mathematical equation parser and evaluator with variable and function support. More...

#include <gin_equationparser.h>

Inheritance diagram for EquationParser:

Public Member Functions
	EquationParser ()
	EquationParser (const juce::String &equation)
	~EquationParser ()
void	defineNameChars (const juce::String &chars)
void	setEquation (const juce::String &equation)
void	clearVariables ()
void	addVariable (const juce::String &name, double *value)
void	setVarFactory (std::function< double *(const char *)> fun)
juce::StringArray	getUsedVariables ()
void	clearConstants ()
void	addConstant (const juce::String &name, double value)
void	addFunction (const juce::String &name, std::function< double(int id, const juce::String &)> fun)
void	addFunction (const juce::String &name, std::function< double(int id)> fun)
void	addFunction (const juce::String &name, std::function< double(int id, double)> fun)
void	addFunction (const juce::String &name, std::function< double(int id, double, double)> fun)
void	addFunction (const juce::String &name, std::function< double(int id, double, double, double)> fun)
void	addFunction (const juce::String &name, std::function< double(int id, double, double, double, double)> fun)
double	evaluate ()
bool	hasError () const
juce::String	getError () const

Detailed Description

Mathematical equation parser and evaluator with variable and function support.

EquationParser provides a flexible system for parsing and evaluating mathematical expressions at runtime. It supports variables, constants, custom functions, and standard mathematical operations. Built on top of muParser library.

Key Features:

• Parse and evaluate mathematical expressions
• Dynamic variable binding (pointers to live values)
• Named constants
• Custom functions with 0-4 parameters or string parameters
• Variable factory for on-demand variable creation
• Comprehensive error handling
• Query which variables are used in an equation

Supported Operations:

• Basic arithmetic: +, -, *, /, ^
• Parentheses for grouping
• Standard math functions (via custom function registration)
• User-defined functions and variables

Usage:

EquationParser parser;
 
// Add variables
double x = 5.0;
parser.addVariable("x", &x);
 
// Add constants
parser.addConstant("pi", 3.14159265359);
 
// Set equation
parser.setEquation("2 * x + pi");
 
// Evaluate
double result = parser.evaluate(); // Returns 13.14159...
 
// Change variable and re-evaluate
x = 10.0;
result = parser.evaluate(); // Returns 23.14159...
 
// Check for errors
if (parser.hasError())
    DBG("Error: " + parser.getError());

Custom Functions:

parser.addFunction("myFunc", [](int id, double a, double b) {
    return a * a + b;
});
parser.setEquation("myFunc(3, 4)");
double result = parser.evaluate(); // Returns 13.0

See also

muParser documentation for expression syntax details

Constructor & Destructor Documentation

EquationParser() [1/2]

EquationParser::EquationParser

(

)

EquationParser() [2/2]

EquationParser::EquationParser

(

const juce::String &

equation

)

~EquationParser()

EquationParser::~EquationParser

(

)

Member Function Documentation

defineNameChars()

void EquationParser::defineNameChars

(

const juce::String &

chars

)

setEquation()

void EquationParser::setEquation

(

const juce::String &

equation

)

clearVariables()

void EquationParser::clearVariables

(

)

addVariable()

void EquationParser::addVariable	(	const juce::String &	name,
		double *	value )

setVarFactory()

void EquationParser::setVarFactory

(

std::function< double *(const char *)>

fun

)

getUsedVariables()

juce::StringArray EquationParser::getUsedVariables

(

)

clearConstants()

void EquationParser::clearConstants

(

)

addConstant()

void EquationParser::addConstant	(	const juce::String &	name,
		double	value )

addFunction() [1/6]

void EquationParser::addFunction	(	const juce::String &	name,
		std::function< double(int id, const juce::String &)>	fun )

addFunction() [2/6]

void EquationParser::addFunction	(	const juce::String &	name,
		std::function< double(int id)>	fun )

addFunction() [3/6]

void EquationParser::addFunction	(	const juce::String &	name,
		std::function< double(int id, double)>	fun )

addFunction() [4/6]

void EquationParser::addFunction	(	const juce::String &	name,
		std::function< double(int id, double, double)>	fun )

addFunction() [5/6]

void EquationParser::addFunction	(	const juce::String &	name,
		std::function< double(int id, double, double, double)>	fun )

addFunction() [6/6]

void EquationParser::addFunction	(	const juce::String &	name,
		std::function< double(int id, double, double, double, double)>	fun )

evaluate()

double EquationParser::evaluate

(

)

hasError()

bool EquationParser::hasError

(

)

const

getError()

juce::String EquationParser::getError

(

)

const

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The documentation for this class was generated from the following file:

• gin_equationparser.h