mei_evaluate.h File Reference

Build an interpreter for a mathematical expression. More...

#include "mei_hash_table.h"
#include "mei_node.h"

Include dependency graph for mei_evaluate.h:

Go to the source code of this file.

Data Structures
struct	mei_tree_t
	Structure defining an interpreter for a mathematical expression. More...

Functions
mei_tree_t *	mei_tree_new (const char *expr)
	Returns a new interpreter. The node member is empty, the string member contains the mathematical expression and the symbol table is initialize with the standard symbols. More...
mei_tree_t *	mei_tree_new_with_shared_symbols (const char *expr, hash_table_t *symbol_table)
	Returns a new interpreter. The node member is empty, the string member contains the mathematical expression and the symbol table is initialize with a existing table, which is shared by multiple interpreter. More...
hash_table_t *	mei_table_symbols_new (void)
	Returns a new table of symbols. The table contains standard mathematical symbols. More...
int	mei_tree_builder (mei_tree_t *ev)
	Call the yacc parser. Return 0 if the parsing is ok, or the number of errors, if errors occurs. More...
void	mei_tree_insert (mei_tree_t *ev, const char *str, const double value)
	Inserts a constant (label and value) in the table of symbols associated to an interpreter. More...
void	mei_symbol_table_insert (hash_table_t *symbol_table, const char *str, const double value)
	Inserts a constant (label and value) in a table of symbols. More...
int	mei_tree_find_symbol (mei_tree_t *ev, const char *str)
	Check if the symbol str exists in the expression stored in ev. More...
int	mei_tree_find_symbols (mei_tree_t *ev, const int size, const char **symbol)
	Check if the symbol str from a list exists in the expression. The list of missing symbols is stored in ev->labels. More...
double	mei_tree_lookup (mei_tree_t *ev, const char *str)
	Returns a value of the str symbol (variable or constant) from table of symbols of ev interpreter. More...
double	mei_evaluate (mei_tree_t *ev)
	Evaluates the expression ev : 1) computes all values for variables inside the expression 2) returns a value from the intrepreted expression. More...
void	mei_tree_destroy (mei_tree_t *ev)
	Free memory and return NULL. More...

Detailed Description

Build an interpreter for a mathematical expression.

Function Documentation

mei_evaluate()

double mei_evaluate

(

mei_tree_t *

ev

)

Evaluates the expression ev : 1) computes all values for variables inside the expression 2) returns a value from the intrepreted expression.

Parameters

[in]

ev

interpreter

Returns

value from the intrepreted expression

mei_symbol_table_insert()

void mei_symbol_table_insert	(	hash_table_t *	symbol_table,
		const char *	str,
		const double	value
	)

Inserts a constant (label and value) in a table of symbols.

Parameters

[in]	symbol_table	table of symbols
[in]	str	label of the constant
[in]	value	value associated to the constant

mei_table_symbols_new()

hash_table_t* mei_table_symbols_new

(

void

)

Returns a new table of symbols. The table contains standard mathematical symbols.

Returns

table of symbols

mei_tree_builder()

int mei_tree_builder

(

mei_tree_t *

ev

)

Call the yacc parser. Return 0 if the parsing is ok, or the number of errors, if errors occurs.

Parameters

[in]

ev

interpreter

Returns

number of parsing errors

mei_tree_destroy()

void mei_tree_destroy

(

mei_tree_t *

ev

)

Free memory and return NULL.

Parameters

[in]

ev

interpreter

mei_tree_find_symbol()

int mei_tree_find_symbol	(	mei_tree_t *	ev,
		const char *	str
	)

Check if the symbol str exists in the expression stored in ev.

Parameters

[in]	ev	interpreter in which we want to know if str exists
[in]	str	symbol to find

Returns

0 if the symbol exists in the symbol table, 1 if not

mei_tree_find_symbols()

int mei_tree_find_symbols	(	mei_tree_t *	ev,
		const int	size,
		const char **	symbol
	)

Check if the symbol str from a list exists in the expression. The list of missing symbols is stored in ev->labels.

Parameters

[in]	ev	interpreter
[in]	size	number of symbols to check
[in]	symbol	list of symbols

Returns

0 if all symbols exist, otherwise return the number of errors

mei_tree_insert()

void mei_tree_insert	(	mei_tree_t *	ev,
		const char *	str,
		const double	value
	)

Inserts a constant (label and value) in the table of symbols associated to an interpreter.

Parameters

[in]	ev	interpreter
[in]	str	label of the constant
[in]	value	value associated to the constant

mei_tree_lookup()

double mei_tree_lookup	(	mei_tree_t *	ev,
		const char *	str
	)

Returns a value of the str symbol (variable or constant) from table of symbols of ev interpreter.

Parameters

[in]	ev	interpreter
[in]	str	name of the symbol

Returns

value of a symbol

mei_tree_new()

mei_tree_t* mei_tree_new

(

const char *

expr

)

Returns a new interpreter. The node member is empty, the string member contains the mathematical expression and the symbol table is initialize with the standard symbols.

Parameters

[in]

expr

string characters of the mathematical expression

Returns

new empty interpreter

mei_tree_new_with_shared_symbols()

mei_tree_t* mei_tree_new_with_shared_symbols	(	const char *const	expr,
		hash_table_t *const	symbol_table
	)

Returns a new interpreter. The node member is empty, the string member contains the mathematical expression and the symbol table is initialize with a existing table, which is shared by multiple interpreter.

Parameters

[in]	expr	string characters of the mathematical expression
[in]	symbol_table	shared table of symbols

Returns

new empty interpreter