o2scl::calculator Class Reference

Evaluate a mathematical expression in a string. More...

#include <shunting_yard.h>

Detailed Description

This is based on Brandon Amos' code at https://github.com/bamos/cpp-expression-parser in turn based on Jesse Brown's code at http://www.daniweb.com/software-development/cpp/code/427500/calculator-using-shunting-yard-algorithm .

The original code has been modified for use in O2scl .

Idea for Future:

Add functions atan2, cot, csc, ceil, floor, int, max, min, and maybe if?

Warning

The nothrow() functions are a naive attempt at more detailed error handling than Amos' original code. I have tried to make sure they don't create any memory leaks, but I have not fully tested this.

Definition at line 119 of file shunting_yard.h.

Public Member Functions
	calculator ()
	Create an empty calculator object.
	calculator (const char *expr, std::map< std::string, double > *vars=0, bool debug=false, std::map< std::string, int > opPrec=opPrecedence)
	Compile expression expr using variables specified in vars. More...
void	compile (const char *expr, std::map< std::string, double > *vars=0, bool debug=false, std::map< std::string, int > opPrec=opPrecedence)
	Compile expression expr using variables specified in vars and return an integer to indicate success or failure.
int	compile_nothrow (const char *expr, std::map< std::string, double > *vars=0, bool debug=false, std::map< std::string, int > opPrec=opPrecedence)
	Compile expression expr using variables specified in vars and return an integer to indicate success or failure.
double	eval (std::map< std::string, double > *vars=0)
	Evalate the previously compiled expression using variables specified in vars. More...
int	eval_nothrow (std::map< std::string, double > *vars, double &result)
	Evalate the previously compiled expression using variables specified in vars. More...
std::string	RPN_to_string ()
	Convert the RPN expression to a string. More...

Static Public Member Functions
static double	calculate (const char *expr, std::map< std::string, double > *vars=0, bool debug=false)
	Compile and evaluate expr using definitions in vars. More...
static int	calculate_nothrow (const char *expr, std::map< std::string, double > *vars, bool debug, double &result)
	Compile and evaluate expr using definitions in vars and return an integer to indicate success or failure.

Static Private Member Functions
static std::map< std::string, int >	buildOpPrecedence ()
	Build the operator precedence map.
static bool	isvariablechar (char c)
	Return true if is a variable.
static double	calculate (TokenQueue_t RPN, std::map< std::string, double > *vars=0)
	Compile and evaluate the expression in RPN using definitions in vars. More...
static int	calculate_nothrow (TokenQueue_t RPN, std::map< std::string, double > *vars, double &result)
	Compile and evaluate the expression in RPN using definitions in vars and return an integer to indicate success or failure. More...
static void	cleanRPN (TokenQueue_t &rpn)
	Empty and free memory associated with rpn. More...
static TokenQueue_t	toRPN (const char *expr, std::map< std::string, double > *vars, bool debug=false, std::map< std::string, int > opPrec=opPrecedence)
	Convert the expression in expr to RPN.
static int	toRPN_nothrow (const char *expr, std::map< std::string, double > *vars, bool debug, std::map< std::string, int > opPrec, TokenQueue_t &queue2)
	Convert the expression in expr to RPN and return an integer to indicate success or failure. More...

Private Attributes
TokenQueue_t	RPN
	The current expression in RPN.

Static Private Attributes
static std::map< std::string, int >	opPrecedence
	A map denoting operator precedence.

Constructor & Destructor Documentation

calculator()

o2scl::calculator::calculator	(	const char *	expr,
		std::map< std::string, double > *	vars = 0,
		bool	debug = false,
		std::map< std::string, int >	opPrec = opPrecedence
	)

Member Function Documentation

calculate() [1/2]

static double o2scl::calculator::calculate ( const char *  expr, std::map< std::string, double > *  vars = 0, bool  debug = false  )

static

calculate() [2/2]

static double o2scl::calculator::calculate ( TokenQueue_t  RPN, std::map< std::string, double > *  vars = 0  )

staticprivate

calculate_nothrow()

static int o2scl::calculator::calculate_nothrow ( TokenQueue_t  RPN, std::map< std::string, double > *  vars, double &  result  )

staticprivate

cleanRPN()

static void o2scl::calculator::cleanRPN ( TokenQueue_t &  rpn )

staticprivate

Note

This is called by the destructor to free the memory in RPN .

eval()

double o2scl::calculator::eval

(

std::map< std::string, double > *

vars = 0

)

eval_nothrow()

int o2scl::calculator::eval_nothrow	(	std::map< std::string, double > *	vars,
		double &	result
	)

RPN_to_string()

std::string o2scl::calculator::RPN_to_string

(

)

Note

This is mostly useful for debugging

toRPN_nothrow()

static int o2scl::calculator::toRPN_nothrow ( const char *  expr, std::map< std::string, double > *  vars, bool  debug, std::map< std::string, int >  opPrec, TokenQueue_t &  queue2  )

staticprivate

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

• /home/awsteiner/wcs/o2scl/src/base/shunting_yard.h