A parser for converting equation strings to postfix. More...

#include <InlineInfixToPostfix.h>

Inheritance diagram for Isis::InlineInfixToPostfix:

Collaboration diagram for Isis::InlineInfixToPostfix:

Public Member Functions
	InlineInfixToPostfix ()
	Constructs an InlineInfixToPostfix object. More...

virtual	~InlineInfixToPostfix ()
	Destroys the InlineInfixToPostfix object. More...

QString	convert (const QString &infix)
	This method converts infix to postfix. More...

QString	tokenizeEquation (const QString &equation)
	This method will add spaces between all operators and numbers, making it possible to get each element of the equation one by one. More...

Protected Member Functions
virtual bool	isKnownSymbol (QString representation)
	This method attempts to verify that the given argument is recognized as a valid function, operator, scalar, or variable. More...

virtual InfixOperator *	findOperator (QString element)
	This method will first search the recognized list of operators and functions for the given token. More...

Protected Attributes
QList< InfixOperator * >	p_operators

Private Member Functions
void	initialize ()
	Adds several infix operators and functions to the operator list that are not already recognized by the parent class, InfixToPostfix. More...

bool	exists (const QString &str)
	Determines whether the given string exists as a recognized variable. More...

bool	isScalar (const QString &scalar)
	Determines whether the given token represents a scalar value (i.e. More...

bool	isVariable (const QString &str)
	Determines whether the given token is a variable and, if so, appends it to the list of variables. More...

Private Attributes
QStringList	m_variables
	The list of variables (represented as strings). More...

Detailed Description

A parser for converting equation strings to postfix.

This class converts infix equations to postfix for parsing.

Author: 2012-07-15 Kris Becker

History:

2012-07-15 Kris Becker - Original version.

2015-03-18 Jeannie Backer - Brought class files closer to ISIS coding standards.

2015-03-24 Jeffrey Covington and Jeannie Backer - Improved documentation.

2015-03-24 Jeannie Backer - Changed m_variables from a QVector to QStringList

2016-02-21 Kristin Berry - Added unitTest.

2017-01-09 Jesse Mapel - Added logical and, or operators. Fixes #4581.

Definition at line 51 of file InlineInfixToPostfix.h.

Constructor & Destructor Documentation

◆ InlineInfixToPostfix()

Isis::InlineInfixToPostfix::InlineInfixToPostfix ( )

Constructs an InlineInfixToPostfix object.

The operators list is filled with string representations of known symbols, recognized by both this class and the parent class.

Definition at line 41 of file InlineInfixToPostfix.cpp.

References initialize().

◆ ~InlineInfixToPostfix()

Isis::InlineInfixToPostfix::~InlineInfixToPostfix ( )

virtual

Destroys the InlineInfixToPostfix object.

Definition at line 49 of file InlineInfixToPostfix.cpp.

Member Function Documentation

◆ convert()

QString Isis::InfixToPostfix::convert ( const QString & infix )

inherited

This method converts infix to postfix.

It uses an enhanced verion of the algorithm found on page 159 of "Data Structures & Algorithms in Java" Second Edition by Robert Lafore. First, we prep the equation with TokenizeEquation and then parse through it using the known-good algorithm.

Parameters

infix The infix equation

Returns: IString The postfix equation

Definition at line 154 of file InfixToPostfix.cpp.

References _FILEINFO_, Isis::IString::Remove(), Isis::toDouble(), Isis::IString::Token(), and Isis::IString::ToQt().

Referenced by Isis::InlineCalculator::toPostfix().

◆ exists()

bool Isis::InlineInfixToPostfix::exists ( const QString & token )

private

Determines whether the given string exists as a recognized variable.

NOTE: This list is constructed using the isVariable() method.

Parameters

token A string token to be compared to the recognized variable list.

Returns: bool Indicates whether the given string is recognized as a variable.

Definition at line 153 of file InlineInfixToPostfix.cpp.

References m_variables.

◆ findOperator()

InfixOperator * Isis::InlineInfixToPostfix::findOperator ( QString token )

protectedvirtual

This method will first search the recognized list of operators and functions for the given token.

If found, it will return a pointer to the represented operator or function. If not found, the method checks whether the given token is a variable. If it is a variable, a new operator is constructed from the given token and a pointer to the represented variable is returned. If the given token is neither an operator, a function nor a variable, then an exception is thrown.

Parameters

token The symbolic representation of the operator, function, or variable

Returns: InfixOperator* A pointer to the operator object that contains known information about the operator

Exceptions

IException::User "The token is not recognized as an operator, function or variable."

Reimplemented from Isis::InfixToPostfix.

Definition at line 98 of file InlineInfixToPostfix.cpp.

References _FILEINFO_, Isis::InfixToPostfix::findOperator(), isVariable(), and Isis::IException::User.

◆ initialize()

void Isis::InlineInfixToPostfix::initialize ( )

private

Adds several infix operators and functions to the operator list that are not already recognized by the parent class, InfixToPostfix.

Definition at line 125 of file InlineInfixToPostfix.cpp.

Referenced by InlineInfixToPostfix().

◆ isKnownSymbol()

bool Isis::InlineInfixToPostfix::isKnownSymbol ( QString representation )

protectedvirtual

This method attempts to verify that the given argument is recognized as a valid function, operator, scalar, or variable.

Parameters

representation The symbolic representation of the operator

Returns: bool Indicates whether the representaion is recognized.

Reimplemented from Isis::InfixToPostfix.

Definition at line 61 of file InlineInfixToPostfix.cpp.

References Isis::InfixToPostfix::isKnownSymbol(), isScalar(), and isVariable().

◆ isScalar()

bool Isis::InlineInfixToPostfix::isScalar ( const QString & token )

private

Determines whether the given token represents a scalar value (i.e.

whether it can be converted to a double).

Parameters

token String to be tested.

Returns: bool Indicates whether the given string can be converted to a double.

Definition at line 166 of file InlineInfixToPostfix.cpp.

References Isis::toDouble().

Referenced by isKnownSymbol().

◆ isVariable()

bool Isis::InlineInfixToPostfix::isVariable ( const QString & token )

private

Determines whether the given token is a variable and, if so, appends it to the list of variables.

A token is considered a variable if it is not a known operator symbol from the parent InfixToPostfix class, not a scalar, and is not empty. Variables are implemented as functions, so new variables are also added to the operators list.

Parameters

token A string containing the token to be tested.

Returns: bool Indicates whether the string was added to the lists of recognized variables and operators.

Definition at line 195 of file InlineInfixToPostfix.cpp.

References m_variables.

Referenced by findOperator(), and isKnownSymbol().

◆ tokenizeEquation()

QString Isis::InfixToPostfix::tokenizeEquation ( const QString & equation )

inherited

This method will add spaces between all operators and numbers, making it possible to get each element of the equation one by one.

It will also parse out the function calls, adding parenthesis where needed so the user doesn't have to. The result is an equation ready for parsing (but NOT fully parenthesized, just enough to make sure our algorithm makes no mistakes).

Parameters

equation An unformatted infix equation

Returns: IString A tokenized equation with additional parentheses

Definition at line 384 of file InfixToPostfix.cpp.

References Isis::IString::DownCase(), and Isis::IString::ToQt().

Member Data Documentation

◆ m_variables

QStringList Isis::InlineInfixToPostfix::m_variables

private

The list of variables (represented as strings).

Definition at line 67 of file InlineInfixToPostfix.h.

Referenced by exists(), and isVariable().

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

src/base/objs/InlineInfixToPostfix/InlineInfixToPostfix.h
src/base/objs/InlineInfixToPostfix/InlineInfixToPostfix.cpp

Public Member Functions

Protected Member Functions

Protected Attributes

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ InlineInfixToPostfix()

◆ ~InlineInfixToPostfix()

Member Function Documentation

◆ convert()

◆ exists()

◆ findOperator()

◆ initialize()

◆ isKnownSymbol()

◆ isScalar()

◆ isVariable()

◆ tokenizeEquation()

Member Data Documentation

◆ m_variables