Converts a string into a NamedFunc. More...

#include <function_parser.hpp>

Public Member Functions
	FunctionParser ()=default

	FunctionParser (const std::string &function_string)
	Standard constructor from string representing a function. More...

	FunctionParser (const FunctionParser &)=default

FunctionParser &	operator= (const FunctionParser &)=default

	FunctionParser (FunctionParser &&)=default

FunctionParser &	operator= (FunctionParser &&)=default

	~FunctionParser ()=default

const std::string &	FunctionString () const
	Get string being parsed. More...

FunctionParser &	FunctionString (const std::string &function_string)
	Set string to be parsed. More...

const std::vector< Token > &	Tokens () const
	Get list of tokens as is at current stage of parsing. More...

Token	ResolveAsToken () const
	Parses provided string into a single Token. More...

NamedFunc	ResolveAsNamedFunc () const
	Parses provided string into a single NamedFunc. More...

Private Member Functions
	FunctionParser (const std::vector< Token > &tokens)
	Constructs FunctionParser from list of Tokens. More...

void	Tokenize () const
	Parses the string into a list of Tokens. More...

void	CheckForUnknowns () const
	Checks that all Tokens were understood. More...

void	ResolveVariables () const
	Generates NamedFunc for each Token representing a constant or Baby variable. More...

void	EvaluateGroupings () const
	Recursively evaluates contents of parenthesis and brackets. More...

void	MergeParentheses () const
	Merges parenthesis Tokens with the contents. More...

void	ApplySubscripts () const
	Merges subscript (bracket) Tokens with the contents. More...

void	DisambiguatePlusMinus () const
	Determines whether "+" and "-" Tokens correspond to unary or binary operators. More...

void	ApplyUnary () const
	Merges unary operator Tokens with their operands. More...

void	MultiplyAndDivide () const
	Merges "*" and "/" Tokens with their operands. More...

void	AddAndSubtract () const
	Merges binary "+" and "-" Tokens with their operands. More...

void	LessGreater () const
	Merges "<", "<=", ">", and ">=" Tokens with their operands. More...

void	EqualOrNot () const
	Merges "==" and "!=" Tokens with their operands. More...

void	And () const
	Merges "&&" Tokens with their operands. More...

void	Or () const
	Merges "\|\|" Tokens with their operands. More...

void	CheckSolved () const
	Check that we have a single Token with a valid NamedFun. More...

void	CleanupName () const
	Restores string representation to initially provided string. More...

void	Solve () const
	Runs full parse from start to finish, caching result. More...

std::size_t	FindClose (std::size_t i_open_token) const
	Find position of closing parenthesis/bracket corresponding to given opening partner. More...

std::string	ConcatenateTokenStrings (std::size_t i_start, std::size_t i_end) const
	Concatenates string representation of Tokens in range [i_start, i_end) More...

void	CondenseTokens (std::size_t i_start, std::size_t i_end, const Token &replacement) const
	Replace Tokens in range [i_start, i_end) with replacement. More...

Private Attributes
std::string	input_string_
	String being parsed. More...

std::vector< Token >	tokens_
	List of tokens generated in parsing process. More...

bool	tokenized_
	String has been parsed into tokens. More...

bool	solved_
	String parsed into tokens, and all tokens succesfully merged. More...

Detailed Description

Converts a string into a NamedFunc.

A FunctionParser is initialized with a string representing a number, variable, function, cut, etc. and converts it to a NamedFunc. It first decomposes the string into components representing single numbers, variables, operators, etc. The components are stored as Tokens. The Tokens representing constants and variables in Baby are processed to obtain valid NamedFuncs. Operators are successively applied following standard order of operations to merge the Tokens into a single Token instance containing a NamedFunc which can return the value represented by the initial string.

Parentheses and brackets are parsed recursively and can be arbitrarily nested.

Currently has support for the basic arithmetic, logical, and comparison operators. Future versions may support ROOT's function syntax, e.g. Sum$(jets_pt).

Definition at line 12 of file function_parser.hpp.

Constructor & Destructor Documentation

FunctionParser::FunctionParser ( )

default

FunctionParser::FunctionParser ( const std::string & function_string )

Standard constructor from string representing a function.

Parameters

[in] function_string String representing a number, variable, function, cut, etc.

Definition at line 41 of file function_parser.cpp.

References input_string_, and ReplaceAll().

FunctionParser::FunctionParser ( const FunctionParser & )

default

FunctionParser::FunctionParser ( FunctionParser && )

default

FunctionParser::~FunctionParser ( )

default

FunctionParser::FunctionParser ( const std::vector< Token > & tokens )

private

Constructs FunctionParser from list of Tokens.

Used by FunctionParser to recursively process lists of Tokens reprenting contents of parentheses or brackets

Parameters

[in] tokens List of Tokens. Should represent a single valid expression

Definition at line 101 of file function_parser.cpp.

References ConcatenateTokenStrings(), input_string_, and tokens_.

Member Function Documentation

void FunctionParser::AddAndSubtract ( ) const

private

Merges binary "+" and "-" Tokens with their operands.

Searches for patten {value}{"+" or "-"}{value} and replaces with single Token

Definition at line 391 of file function_parser.cpp.

References Token::binary_minus, Token::binary_plus, CondenseTokens(), Token::function_, Token::resolved_scalar, Token::resolved_vector, tokens_, and Token::type_.

Referenced by Solve().

void FunctionParser::And ( ) const

private

Merges "&&" Tokens with their operands.

Searches for patten {value}{&&}{value} and replaces with single Token

Definition at line 477 of file function_parser.cpp.

References CondenseTokens(), Token::function_, Token::logical_and, Token::resolved_scalar, Token::resolved_vector, tokens_, and Token::type_.

Referenced by Solve().

void FunctionParser::ApplySubscripts ( ) const

private

Merges subscript (bracket) Tokens with the contents.

Searches for patten {open bracket}{value}{close bracket} and replaces with single Token

Definition at line 242 of file function_parser.cpp.

References Token::close_square, ConcatenateTokenStrings(), CondenseTokens(), Token::function_, Token::open_square, Token::resolved_scalar, Token::resolved_vector, NamedFunc::ScalarFunction(), tokens_, Token::type_, and NamedFunc::VectorFunction().

Referenced by Solve().

void FunctionParser::ApplyUnary ( ) const

private

Merges unary operator Tokens with their operands.

Searches for patten {unary operator}{value} and replaces with single Token

Definition at line 334 of file function_parser.cpp.

References CondenseTokens(), Token::function_, Token::logical_not, Token::resolved_scalar, Token::resolved_vector, tokens_, Token::type_, Token::unary_minus, and Token::unary_plus.

Referenced by Solve().

void FunctionParser::CheckForUnknowns ( ) const

private

Checks that all Tokens were understood.

Definition at line 167 of file function_parser.cpp.

References ERROR, input_string_, tokens_, and Token::unknown.

Referenced by Solve().

void FunctionParser::CheckSolved ( ) const

private

Check that we have a single Token with a valid NamedFun.

Definition at line 525 of file function_parser.cpp.

References DBG, ERROR, Token::resolved_scalar, Token::resolved_vector, and tokens_.

Referenced by Solve().

void FunctionParser::CleanupName ( ) const

private

Restores string representation to initially provided string.

Token merging process often generates unnecessary parentheses in string, so just use the original string

Definition at line 545 of file function_parser.cpp.

References input_string_, and tokens_.

Referenced by Solve().

string FunctionParser::ConcatenateTokenStrings	(	std::size_t	i_start,
		std::size_t	i_end
	)		const

private

Concatenates string representation of Tokens in range [i_start, i_end)

Parameters

[in]	i_start	Position of starting Token (inclusive)
[in]	i_end	Position of ending Token (exclusive)

Returns: Concatentation of string representations of Tokens in range [i_start, i_end)

Definition at line 628 of file function_parser.cpp.

References tokens_.

Referenced by ApplySubscripts(), FunctionParser(), and MergeParentheses().

void FunctionParser::CondenseTokens	(	std::size_t	i_start,
		std::size_t	i_end,
		const Token &	replacement
	)		const

private

Replace Tokens in range [i_start, i_end) with replacement.

Parameters

[in]	i_start	Position of starting Token (inclusive)
[in]	i_end	Position of ending Token (exclusive)
[in]	replacement	Token which replaces the range

Definition at line 645 of file function_parser.cpp.

References tokens_.

Referenced by AddAndSubtract(), And(), ApplySubscripts(), ApplyUnary(), EqualOrNot(), EvaluateGroupings(), LessGreater(), MergeParentheses(), MultiplyAndDivide(), and Or().

void FunctionParser::DisambiguatePlusMinus ( ) const

private

Determines whether "+" and "-" Tokens correspond to unary or binary operators.

Definition at line 271 of file function_parser.cpp.

References Token::ambiguous_minus, Token::ambiguous_plus, Token::binary_minus, Token::binary_plus, Token::close_paren, Token::close_square, Token::divide, Token::equal, Token::greater, Token::greater_equal, Token::less, Token::less_equal, Token::logical_and, Token::logical_not, Token::logical_or, Token::modulus, Token::multiply, Token::not_equal, Token::number, Token::open_paren, Token::open_square, Token::resolved_scalar, Token::resolved_vector, tokens_, Token::type_, Token::unary_minus, Token::unary_plus, Token::unknown, and Token::variable_name.

Referenced by Solve().

void FunctionParser::EqualOrNot ( ) const

private

Merges "==" and "!=" Tokens with their operands.

Searches for patten {value}{comparison}{value} and replaces with single Token

Definition at line 450 of file function_parser.cpp.

References CondenseTokens(), Token::equal, Token::function_, Token::not_equal, Token::resolved_scalar, Token::resolved_vector, tokens_, and Token::type_.

Referenced by Solve().

void FunctionParser::EvaluateGroupings ( ) const

private

Recursively evaluates contents of parenthesis and brackets.

Definition at line 197 of file function_parser.cpp.

References CondenseTokens(), FindClose(), ResolveAsToken(), and tokens_.

Referenced by Solve().

size_t FunctionParser::FindClose ( std::size_t i_open_token ) const

private

Find position of closing parenthesis/bracket corresponding to given opening partner.

Parameters

[in] i_open_token Position in current list of Tokens of opening parenthesis/bracket

Returns: Position in current list of Tokens of closing parenthesis/bracket

Definition at line 583 of file function_parser.cpp.

References Token::close_paren, Token::close_square, Token::open_paren, Token::open_square, and tokens_.

Referenced by EvaluateGroupings().

const string & FunctionParser::FunctionString ( ) const

Get string being parsed.

Returns: String being parsed

Definition at line 53 of file function_parser.cpp.

References input_string_.

Referenced by operator<<().

FunctionParser & FunctionParser::FunctionString ( const std::string & function_string )

Set string to be parsed.

Parameters

[in] function_string String to be parsed

Returns: Reference to *this

Definition at line 61 of file function_parser.cpp.

References input_string_, ReplaceAll(), solved_, and tokenized_.

void FunctionParser::LessGreater ( ) const

private

Merges "<", "<=", ">", and ">=" Tokens with their operands.

Searches for patten {value}{comparison}{value} and replaces with single Token

Definition at line 419 of file function_parser.cpp.

References CondenseTokens(), Token::function_, Token::greater, Token::greater_equal, Token::less, Token::less_equal, Token::resolved_scalar, Token::resolved_vector, tokens_, and Token::type_.

Referenced by Solve().

void FunctionParser::MergeParentheses ( ) const

private

Merges parenthesis Tokens with the contents.

Searches for patten {open paren}{value}{close paren} and replaces with single Token

Definition at line 214 of file function_parser.cpp.

References Token::close_paren, ConcatenateTokenStrings(), CondenseTokens(), Token::function_, NamedFunc::Name(), Token::open_paren, Token::resolved_scalar, Token::resolved_vector, tokens_, and Token::type_.

Referenced by Solve().

void FunctionParser::MultiplyAndDivide ( ) const

private

Merges "*" and "/" Tokens with their operands.

Searches for patten {value}{"*" or "/"}{value} and replaces with single Token

Definition at line 361 of file function_parser.cpp.

References CondenseTokens(), Token::divide, Token::function_, Token::modulus, Token::multiply, Token::resolved_scalar, Token::resolved_vector, tokens_, and Token::type_.

Referenced by Solve().

FunctionParser& FunctionParser::operator= ( const FunctionParser & )

default

FunctionParser& FunctionParser::operator= ( FunctionParser && )

default

void FunctionParser::Or ( ) const

private

Merges "||" Tokens with their operands.

Searches for patten {value}{||}{value} and replaces with single Token

Definition at line 502 of file function_parser.cpp.

References CondenseTokens(), Token::function_, Token::logical_or, Token::resolved_scalar, Token::resolved_vector, tokens_, and Token::type_.

Referenced by Solve().

NamedFunc FunctionParser::ResolveAsNamedFunc ( ) const

Parses provided string into a single NamedFunc.

Definition at line 84 of file function_parser.cpp.

References input_string_, Solve(), and tokens_.

Token FunctionParser::ResolveAsToken ( ) const

Parses provided string into a single Token.

Definition at line 77 of file function_parser.cpp.

References Solve(), and tokens_.

Referenced by EvaluateGroupings().

void FunctionParser::ResolveVariables ( ) const

private

Generates NamedFunc for each Token representing a constant or Baby variable.

Definition at line 178 of file function_parser.cpp.

References Baby::GetFunction(), Token::number, Token::resolved_scalar, Token::resolved_vector, tokens_, and Token::variable_name.

Referenced by Solve().

void FunctionParser::Solve ( ) const

private

Runs full parse from start to finish, caching result.

Definition at line 554 of file function_parser.cpp.

References AddAndSubtract(), And(), ApplySubscripts(), ApplyUnary(), CheckForUnknowns(), CheckSolved(), CleanupName(), DisambiguatePlusMinus(), EqualOrNot(), EvaluateGroupings(), LessGreater(), MergeParentheses(), MultiplyAndDivide(), Or(), ResolveVariables(), solved_, and Tokenize().

Referenced by ResolveAsNamedFunc(), and ResolveAsToken().

void FunctionParser::Tokenize ( ) const

private

Parses the string into a list of Tokens.

Definition at line 111 of file function_parser.cpp.

References Token::GetType(), Token::greater, input_string_, Token::less, Token::logical_not, Token::number, tokenized_, tokens_, Token::unknown, and Token::variable_name.

Referenced by Solve().

const vector< Token > & FunctionParser::Tokens ( ) const

Get list of tokens as is at current stage of parsing.

Definition at line 71 of file function_parser.cpp.

References tokens_.

Referenced by operator<<().

Member Data Documentation

std::string FunctionParser::input_string_

private

String being parsed.

Definition at line 31 of file function_parser.hpp.

Referenced by CheckForUnknowns(), CleanupName(), FunctionParser(), FunctionString(), ResolveAsNamedFunc(), and Tokenize().

bool FunctionParser::solved_

mutableprivate

String parsed into tokens, and all tokens succesfully merged.

Definition at line 34 of file function_parser.hpp.

Referenced by FunctionString(), and Solve().

bool FunctionParser::tokenized_

mutableprivate

String has been parsed into tokens.

Definition at line 33 of file function_parser.hpp.

Referenced by FunctionString(), and Tokenize().

std::vector<Token> FunctionParser::tokens_

mutableprivate

List of tokens generated in parsing process.

Definition at line 32 of file function_parser.hpp.

Referenced by AddAndSubtract(), And(), ApplySubscripts(), ApplyUnary(), CheckForUnknowns(), CheckSolved(), CleanupName(), ConcatenateTokenStrings(), CondenseTokens(), DisambiguatePlusMinus(), EqualOrNot(), EvaluateGroupings(), FindClose(), FunctionParser(), LessGreater(), MergeParentheses(), MultiplyAndDivide(), Or(), ResolveAsNamedFunc(), ResolveAsToken(), ResolveVariables(), Tokenize(), and Tokens().

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

inc/core/function_parser.hpp
src/core/function_parser.cpp

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation