Main functionality of this library. More...

#include <pssmathparser.h>

Inheritance diagram for PssMathParser::MathExpression:

Collaboration diagram for PssMathParser::MathExpression:

Public Member Functions
	MathExpression ()
	Constructor, constructor list only. More...

	~MathExpression ()
	Destructor.

const string	expression () const
	Getter of the loaded expression. More...

void	setExpression (const string &a_expression)
	Load the infix expression to the object. More...

void	setMath (const string &a_expression)
	Does all the steps needed to produce a result. More...

const string	reversePolish () const
	Getter of the expression in reverse Polish notation. More...

bool	setArgumentMap (const string &a_reversePolish)
	Setter of the Argument Map from user input of reverse polish. More...

bool	setArgumentMap ()
	Populates the m_argumentMap. More...

bool	expressionToReversePolish ()
	Creates the Reverse polish notation of the expression. More...

double	calculateExpression ()
	Calculates the expression. More...

uint32_t	reversePolishErrorNum ()
	Getter of m_reversePolishErrorNum. More...

const string	reversePolishErrorString ()
	Getter of m_reversePolishErrorString. More...

uint32_t	expressionErrorNum ()
	Getter of m_expressionErrorNum. More...

const string	expressionErrorString ()
	Getter of m_expressionErrorString. More...

const string	mathToString () const
	Gets the vector m_math into string. More...

const string	mathToStringFull () const
	Gets the vector m_math into string, with explanation of elements. More...

bool	expandMathExpression ()
	Expands the math expression with generated arguments. More...

void	clear ()
	Clears all containters from data.

void	setMathPrintPrecision (const uint16_t &mathPrintPrecision)
	Sets the precission (digits after comma) when printing numbers. More...

uint16_t	getMathPrintPrecision () const
	Get the math precision for printing. More...

void	setVariableDouble (const string &a_name, const double a_value)
	Sets the value of the variable from the argument map. More...

uint16_t	getVariableSize () const
	Return the number of variables in the argumentMap.

Public Member Functions inherited from PssMathParser::MathParser
virtual	~MathParser ()=0
	Virtual destructor because this class is pure virtual.

Static Public Member Functions
static double	add (const double a_arg1, const double a_arg2)
	Overloaded addition of two doubles. More...

static double	subtract (const double a_arg1, const double a_arg2)
	Overloaded subtraction of two doubles. More...

static double	multiply (const double a_arg1, const double a_arg2)
	Overloaded multiplication of two doubles. More...

static double	divide (const double a_arg1, const double a_arg2)
	Overloaded division of two doubles. More...

static bool	isNumber (const string &a_str)
	Check if string is number. More...

static bool	isSpecialCharacter (const char &a_char)
	Checks if the character exists in the vector of special chars. More...

static bool	isSpecialNoParenthesis (const char &a_char)
	isSpecialCharacter but exclude parenthesis More...

static double	convertStringToDouble (const string &a_str)
	Convert string to double using atof() More...

static double	getResultdddOperator (double a_arg1, double a_arg2, const string &a_operatorKey)
	Returns the value of the function that operates on two args. More...

Static Public Member Functions inherited from PssMathParser::MathParser
static MathParser *	makeMathParser ()
	Factory constructor. More...

Static Public Attributes
static vector< char >	specialChars
	Special characters found in the infix notation. More...

static unordered_map< string, Operator >	operatorMap
	Available operators in a map. More...

static unordered_map< string, Argument >	constantMap
	Available constants in a map. More...

Private Member Functions
size_t	operatorMapSize ()
	Getter of the operatorMap number of elements (size) More...

bool	hasOperatorMap (const string &a_operatorName) const
	Tests if the operatorMap has an operator with the given name. More...

bool	hasConstantMap (const string &a_constantName) const
	Tests if the constantMap has a constant with the given name. More...

bool	hasArgumentMap (const string &a_argumentName) const
	Tests if the m_argumentMap has an argument with the given name. More...

bool	hasGeneratorMap (const string &a_generatorName) const
	Tests if the m_generatorVec has a generator with the given name. More...

bool	isOperator (const string a_entityName) const
	Tests if the given name is an Operator. More...

bool	isArgument (const string a_entityName) const
	Tests if the given name is an Argument. More...

bool	isGenerator (const string a_entityName) const
	Tests if the given name is an Generator. More...

bool	isOperatorOneArg (const string a_entityName) const
	Checks if the operator operates on one arg. More...

bool	isOperatorTwoArg (const string a_entityName) const
	Checks if the operator operates on two args. More...

bool	generateArgArgOp (const string &a_key1, const string &a_key2, const string &a_key3)
	Generates an Argument that is connected to a generator. More...

bool	generateArgOp (const string &a_key1, const string &a_key2)
	Generates an Argument that is connected to a generator. More...

double	getArgumentDoubleValue (const string &a_key) const
	Getter of the Argument m_dvalue. More...

double	getConstantDoubleValue (const string &a_key) const
	Getter of the constant double value. More...

const Argument *	getConstant (const string &a_key) const
	Gets pointer to the constant. More...

const Operator *	getOperator (const string &a_key) const
	Gets pointer to the operator. More...

Generator *	getGenerator (const string &a_key)
	Gets pointer to the generator. More...

const Argument *	getArgument (const string &a_key) const
	Gets pointer to the argument. More...

uint16_t	getEntitySize (EntityType a_entityType) const
	Gets the number of specific entities. More...

EntityType	entityType (const string &a_key) const
	Getter of the EntityType. More...

void	setDoubleValueToArgument (const string &a_key, const double a_value)
	Setter of the m_dvalue of Argument. More...

const string	createNewUserConstantName () const
	Creates new names for internaly defined arguments. More...

bool	pushToReversePolish (const string &a_str, const char &a_char)
	Converts infix notation to Reverse Polish. More...

void	appendToReversePolishString (const string &a_str)
	Appends elements to the Reverse Polish separated by space. More...

Private Attributes
uint32_t	m_reversePolishError

string	m_reversePolishErrorString

uint32_t	m_expressionError

string	m_expressionErrorString

string	m_expression

string	m_reversePolish

uint16_t	m_mathPrintPrecision

unordered_map< string, Argument >	m_argumentMap

vector< Generator >	m_generatorVec

vector< string >	m_math

vector< string >	m_RPstack

Detailed Description

Main functionality of this library.

Everything from parsing expressions, converting to Reverse Polish notation and contruction of maps of generator for fast calculation is done here.

Constructor & Destructor Documentation

MathExpression::MathExpression ( )

Constructor, constructor list only.

Set the errors to zero

Member Function Documentation

double MathExpression::add	(	const double	a_arg1,
		const double	a_arg2
	)

static

Overloaded addition of two doubles.

Parameters

a_arg1
a_arg2

Returns: a_arg1+a_arg2

void MathExpression::appendToReversePolishString ( const string & a_str )

private

Appends elements to the Reverse Polish separated by space.

Parameters

a_str Entity to be apended

double MathExpression::calculateExpression ( )

virtual

Calculates the expression.

This function calculates all the generators from the generator map going successively which yields in the end the result of the calculation of the whole expression.

Returns: double The result of the calculation, i.e. the value of the last argument in the map

Implements PssMathParser::MathParser.

double MathExpression::convertStringToDouble ( const string & a_str )

static

Convert string to double using atof()

Parameters

a_str

Returns: double Value of the conversion

const string MathExpression::createNewUserConstantName ( ) const

private

Creates new names for internaly defined arguments.

Counts how many arguments are there and creates one from the new available name. Available names are of the form #AA, #AB, #AC, ..., #BA, #BB, ...

Returns: string The new name

double MathExpression::divide	(	const double	a_arg1,
		const double	a_arg2
	)

static

Overloaded division of two doubles.

Parameters

a_arg1
a_arg2

Returns: a_arg1/a_arg2

EntityType MathExpression::entityType ( const string & a_key ) const

private

Getter of the EntityType.

Parameters

a_key Name of the entity

Returns: EntityType Return of the entityType()

bool MathExpression::expandMathExpression ( )

virtual

Expands the math expression with generated arguments.

This function extracts the expression to calculation steps. It expands the m_math expression to a one-step calculations arguments (generated arguments) and unused operators. These arguments don't exist in the original expression but represent in-between steps of calculation (temporary varables). The extended expression ends with an argument which is the result of the calculation. This way we form a structure that can later be used as an arbitrary function for any user input variables.

Example 1:

infix expression: (10 + 2) - 3 + 5
reverse polish: 10 2 + 3 - 5 +
expanded math: 10 2 + 3 - 5 + a 3 - 5 + c 5 + d (where: a=10+2; c=a-3; d=c+5;)

Example 2:

infix expression: 162 / (2 + 1 ) ^4
reverse polish: 162 2 1 + 4 ^ /
expanded math: 162 2 1 + 4 ^ / 162 a 4 ^ / 162 b / c (where: a=2+1; b=a^4; c=162/b;)

Returns: true If successful expression extraction; false If some error happened. This sets the members m_expressionError and m_expressionErrorString

Implements PssMathParser::MathParser.

const string MathExpression::expression ( ) const

virtual

Getter of the loaded expression.

Returns: string The loaded infix m_expression of the object

Implements PssMathParser::MathParser.

uint32_t MathExpression::expressionErrorNum ( )

Getter of m_expressionErrorNum.

Returns: uint32_t The m_expressionError

const string MathExpression::expressionErrorString ( )

Getter of m_expressionErrorString.

Returns: string The m_expressionErrorString

bool MathExpression::expressionToReversePolish ( )

virtual

Creates the Reverse polish notation of the expression.

Start parsing the infix notation. On every full argument or operator (entity) that is found, a call to the pushToReversePolish function is performed to reorder the entities in a reverse polish notation. This function can change the setted expression. One change is adding 0 in front of signed variables thus making a sign into an operator. Other change is adding parenthesis arround the ^ operator because it is right to left operator (meaning 2^3^4 = 2^(3^4)). Main functionality of this algorithm is to recognize separate entities from the infix notation. Then it sends this data to the pushToReversePolish which only rearanges the entries by preceedence and parenthesis.

Returns: true Successful creation of the reverse polish; false Some error occured

Implements PssMathParser::MathParser.

bool MathExpression::generateArgArgOp	(	const string &	a_key1,
		const string &	a_key2,
		const string &	a_key3
	)

private

Generates an Argument that is connected to a generator.

Creates new argument and ads it to the m_argumentMap. Ads the generator to he m_generattorMap. Ads entity to the m_math.

Parameters

a_key1	Argument 1 name
a_key2	Argument 2 name
a_key3	Operator name

Returns: true All went ok; false Some error happened

bool MathExpression::generateArgOp	(	const string &	a_key1,
		const string &	a_key2
	)

private

Generates an Argument that is connected to a generator.

Creates new argument and ads it to the m_argumentMap. Ads the generator to the m_generattorMap. Ads entity to the m_math.

Parameters

a_key1	Argument name
a_key2	Operator name

Returns: true All went ok; false Some error happened

const Argument * MathExpression::getArgument ( const string & a_key ) const

private

Gets pointer to the argument.

Parameters

a_key Name of the argument

Returns: *Argument If the argument exists in m_argumentMap; nullptr If the argument doesn't exist

double MathExpression::getArgumentDoubleValue ( const string & a_key ) const

private

Getter of the Argument m_dvalue.

Parameters

a_key Name of the argument

Returns: double Value of m_dvalue

const Argument * MathExpression::getConstant ( const string & a_key ) const

private

Gets pointer to the constant.

Parameters

a_key Name of the constant

Returns: *Argument If the constant exists in constantMap; nullptr If the constant doesn't exist

double MathExpression::getConstantDoubleValue ( const string & a_key ) const

private

Getter of the constant double value.

Parameters

a_key Name of the constant

Returns: double Value of the constant

uint16_t MathExpression::getEntitySize ( EntityType a_entityType ) const

private

Gets the number of specific entities.

This is used to count the Arguments for creating a new argument.

Parameters

a_entityType This is one of the entities

Returns: uint16_t Number of entities

Generator * MathExpression::getGenerator ( const string & a_key )

private

Gets pointer to the generator.

Parameters

a_key Name of the generator

Returns: *Generator If the generator exists in m_generatorVec; nullptr If the generator doesn't exist

uint16_t MathExpression::getMathPrintPrecision ( ) const

virtual

Get the math precision for printing.

Returns: uint16_t The precision when printing

Implements PssMathParser::MathParser.

const Operator * MathExpression::getOperator ( const string & a_key ) const

private

Gets pointer to the operator.

Parameters

a_key Name of the operator

Returns: *Operator If the operator exists in operatorMap; nullptr If the operator doesn't exist

double MathExpression::getResultdddOperator	(	double	a_arg1,
		double	a_arg2,
		const string &	a_operatorKey
	)

static

Returns the value of the function that operates on two args.

Parameters

a_arg1	First argument
a_arg2	Secont Argument
a_operatorKey	Name of the operator or function

Returns: double Result of the function(a_arg1, a_arg2)

bool MathExpression::hasArgumentMap ( const string & a_argumentName ) const

private

Tests if the m_argumentMap has an argument with the given name.

Parameters

a_argumentName Name of the tested argument

Returns: true Exists argument with the given name; false Doesn't exist argument with the given name

bool MathExpression::hasConstantMap ( const string & a_constantName ) const

private

Tests if the constantMap has a constant with the given name.

Parameters

a_constantName Name of the tested constant

Returns: true Exists constant with the given name; false Doesn't exist constant with the given name

bool MathExpression::hasGeneratorMap ( const string & a_generatorName ) const

private

Tests if the m_generatorVec has a generator with the given name.

Parameters

a_generatorName Name of the tested generator

Returns: true Exists generator with the given name; false Doesn't exist generator with the given name

bool MathExpression::hasOperatorMap ( const string & a_operatorName ) const

private

Tests if the operatorMap has an operator with the given name.

Parameters

a_operatorName Name of the tested operator

Returns: true Exists operator with the given name; false Doesn't exist operator with the given name

bool MathExpression::isArgument ( const string a_entityName ) const

private

Tests if the given name is an Argument.

Arguments are either in the m_argumentMap or in the constantMap. We check if in one of these maps.

Parameters

a_entityName The name of the entity to be checked

Returns: true It is an argument; false It is not an argument

bool MathExpression::isGenerator ( const string a_entityName ) const

private

Tests if the given name is an Generator.

This is same as hasGeneratorMap function, but is here for completness with other functions.

Parameters

a_entityName The name of the entity to be checked

Returns: true It is a generator; false It is not a generator

bool MathExpression::isNumber ( const string & a_str )

static

Check if string is number.

Parameters

a_str String to test if it is number

Returns: true Is number; false Is not number

bool MathExpression::isOperator ( const string a_entityName ) const

private

Tests if the given name is an Operator.

This is same as hasOperatorMap function, but is here for completness with other functions.

Parameters

a_entityName The name of the entity to be checked

Returns: true It is an operator; false It is not an operator

bool MathExpression::isOperatorOneArg ( const string a_entityName ) const

private

Checks if the operator operates on one arg.

Parameters

a_entityName The operator name

Returns: true Operates on one arg; false Doesn't operate on one arg

bool MathExpression::isOperatorTwoArg ( const string a_entityName ) const

private

Checks if the operator operates on two args.

Parameters

a_entityName The operator name

Returns: true Operates on two args; false Doesn't operate on two args

bool MathExpression::isSpecialCharacter ( const char & a_char )

static

Checks if the character exists in the vector of special chars.

Parameters

a_char

Returns: true Character is special; false Character doesn't exist in the vector of special chars

bool MathExpression::isSpecialNoParenthesis ( const char & a_char )

static

isSpecialCharacter but exclude parenthesis

Parameters

a_char

Returns: true Character is special; false Character doesn't exist in the vector of special chars

const string MathExpression::mathToString ( ) const

virtual

Gets the vector m_math into string.

Returns: string String of elements of m_math separated by coma

Implements PssMathParser::MathParser.

const string MathExpression::mathToStringFull ( ) const

virtual

Gets the vector m_math into string, with explanation of elements.

Returns: string String of elements of m_math separated by coma with explanation

Implements PssMathParser::MathParser.

double MathExpression::multiply	(	const double	a_arg1,
		const double	a_arg2
	)

static

Overloaded multiplication of two doubles.

Parameters

a_arg1
a_arg2

Returns: a_arg1*a_arg2

size_t MathExpression::operatorMapSize ( )

private

Getter of the operatorMap number of elements (size)

Returns: size_t Unsigned int, the operatorMap size

bool MathExpression::pushToReversePolish	(	const string &	a_str,
		const char &	a_char
	)

private

Converts infix notation to Reverse Polish.

Uses the Shunting-yard algorithm to reorder infix notation coming successively as it is written. The algorithm needs first to recognize the type of the argument (variable, constant, operator...). Then it parses the operator precednce and pushes to stack. The m_RPstack acts as containter while the infix is being read. The RP notation is build in the m_reversePolish as a string.

The algorithm shorlty goes as follows:

``` if a_str is a number or variable then push it to the front of the output; else if a_str is an operator, then: find the first '(' and make this position iend or if there is no '(' make end of the stack position the iend; loop from i=0 to iend: if the i operator from the stack has greater than or equal precedence than a_str: pop from front of the operators stack onto the output queue; reset i and iend because of poping the operator stack; push to front the operator a_str; else if a_str is '(' push to front of stack; else if a_str is ')': pop from front of stack to output until the first '('; if there is no '(' then raise error;

if it is the last entry from the infix push all stack entries to the output; ```

Parameters

a_str	Variable, constant, number or operator as a string
a_char	Explains the a_str ('n'=number, 's'=special, 'a'=alpha, 'N'=last number, 'S'=last special, 'A'=last alpha)

Returns: true Construction of RP is ok; false Construction of the RP went wrong

const string MathExpression::reversePolish ( ) const

virtual

Getter of the expression in reverse Polish notation.

Returns: m_reversePolish The string that is the reverse polish of the m_expression

Implements PssMathParser::MathParser.

uint32_t MathExpression::reversePolishErrorNum ( )

Getter of m_reversePolishErrorNum.

Returns: uint32_t The m_reversePolishError

const string MathExpression::reversePolishErrorString ( )

Getter of m_reversePolishErrorString.

Returns: string The m_reversePolishErrorString

bool MathExpression::setArgumentMap ( const string & a_reversePolish )

virtual

Setter of the Argument Map from user input of reverse polish.

This function exist if you want to load the m_argumentMap from polish notation from the user string input and not to be calculated from the infix. This also sets the m_reversePolish to the given input.

Parameters

a_reversePolish The reverse polish with space as a separator

Returns: true Everything was ok; false Some error

Implements PssMathParser::MathParser.

bool MathExpression::setArgumentMap ( )

virtual

Populates the m_argumentMap.

Traverses the m_reversePolish notation and creates internally defined variables, constants and user defined constants. This new names are written in the map m_math.

Returns: true Everything was ok; false Some error

Implements PssMathParser::MathParser.

void MathExpression::setDoubleValueToArgument	(	const string &	a_key,
		const double	a_value
	)

private

Setter of the m_dvalue of Argument.

Parameters

a_key	Name of the argument
a_value	Value to set

void MathExpression::setExpression ( const string & a_expression )

virtual

Load the infix expression to the object.

Clear the m_expression. Set m_expression and remove spaces and tabs.

Parameters

a_expression String with the infix expression

Implements PssMathParser::MathParser.

void MathExpression::setMath ( const string & a_expression )

virtual

Does all the steps needed to produce a result.

These are the steps that produce full expression that can give result:

```c++ setExpression(a_expression); expressionToReversePolish(); setArgumentMap(); expandMathExpression(); ```

Parameters

a_expression

Implements PssMathParser::MathParser.

void MathExpression::setMathPrintPrecision ( const uint16_t & mathPrintPrecision )

virtual

Sets the precission (digits after comma) when printing numbers.

Parameters

mathPrintPrecision Integer of precission default is 7

Implements PssMathParser::MathParser.

void MathExpression::setVariableDouble	(	const string &	a_name,
		const double	a_value
	)

virtual

Sets the value of the variable from the argument map.

Parameters

a_name	Name of the variable
a_value	Value of the variable (double)

Implements PssMathParser::MathParser.

double MathExpression::subtract	(	const double	a_arg1,
		const double	a_arg2
	)

static

Overloaded subtraction of two doubles.

Parameters

a_arg1
a_arg2

Returns: a_arg1-a_arg2

Member Data Documentation

unordered_map< string, Argument > MathExpression::constantMap

static

Available constants in a map.

Defined constants

The map hold the constant name as a key. The map values are preset here. These keys are also reserved words for the writing expressions.

unordered_map<string, Argument> PssMathParser::MathExpression::m_argumentMap

private

Map of Arguments

string PssMathParser::MathExpression::m_expression

private

The infix notation

uint32_t PssMathParser::MathExpression::m_expressionError

private

Error num in the infix notation

string PssMathParser::MathExpression::m_expressionErrorString

private

Error string in the infix notation

vector<Generator> PssMathParser::MathExpression::m_generatorVec

private

Vector of generators

vector<string> PssMathParser::MathExpression::m_math

private

The expression in entities

uint16_t PssMathParser::MathExpression::m_mathPrintPrecision

private

Precision when printing numbers

string PssMathParser::MathExpression::m_reversePolish

private

The RP notation

uint32_t PssMathParser::MathExpression::m_reversePolishError

private

Error num in the RP notation

string PssMathParser::MathExpression::m_reversePolishErrorString

private

Error string in the RP notation

vector<string> PssMathParser::MathExpression::m_RPstack

private

Stack for the Shunting-yard algorithm

unordered_map< string, Operator > MathExpression::operatorMap

static

Available operators in a map.

Defined operators

The map hold the operator name as a key. The map values are set to point to a function. These keys are also reserved words for the writing expressions.

vector< char > MathExpression::specialChars

static

Initial value:

=
{
    '+',
    '-',
    '*',
    '/',
    '^',
    '(',
    ')'
}

Special characters found in the infix notation.

Special characters

The vector holds the special characters in the infix notation. Operators and parenthesis.

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

Public Member Functions

Static Public Member Functions

Static Public Attributes

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation