Package org.mariuszgromada.math.mxparser

Class Constant

  • All Implemented Interfaces:
    java.io.Serializable
    public class Constant
extends PrimitiveElement
implements java.io.Serializable
    Constant class provides ability to declare constants. Constants can be used in further processing by any expression, dependent or recursive argument, function, etc...

    When creating a constant you should avoid names reserved as parser keywords, in general words known in mathematical language as function names, operators (for example: sin, cos, +, -, pi, e, etc...). Please be informed that after associating the constant with the expression, function or dependent/recursive argument its name will be recognized by the parser as reserved key word. It means that it could not be the same as any other key word known by the parser for this particular expression.

    Version:
    6.1.0
    See Also:
    RecursiveArgument, Expression, Function, Argument, Serialized Form

    • Field Detail

      • serialVersionUID

        private static final long serialVersionUID

      • NOT_FOUND

        public static final int NOT_FOUND
        When constant could not be found
        See Also:
        Constant Field Values

      • TYPE_DESC

        public static java.lang.String TYPE_DESC

      • NO_SYNTAX_ERRORS

        public static final boolean NO_SYNTAX_ERRORS
        Status of the syntax - no syntax error
        See Also:
        Constant Field Values

      • SYNTAX_ERROR

        public static final boolean SYNTAX_ERROR
        Status of the syntax - syntax error
        See Also:
        Constant Field Values

      • SYNTAX_ERROR_OR_STATUS_UNKNOWN

        @Deprecated
public static final boolean SYNTAX_ERROR_OR_STATUS_UNKNOWN
        Deprecated.
        Planned to be removed, use SYNTAX_ERROR instead
        Status of the syntax - syntax error
        See Also:
        Constant Field Values

      • constantName

        private java.lang.String constantName
        Name of the constant

      • constantValue

        private double constantValue
        Constant value

      • description

        private java.lang.String description
        Constant description

      • relatedExpressionsList

        private java.util.List<Expression> relatedExpressionsList
        Dependent expression list

      • syntaxStatus

        private boolean syntaxStatus
        Status of the expression syntax Please referet to the: - NO_SYNTAX_ERRORS - SYNTAX_ERROR

      • errorMessage

        private java.lang.String errorMessage
        Message after checking the syntax

    • Constructor Detail

      • Constant

        public Constant​(java.lang.String constantName,
                double constantValue)
        Constructor - creates constant with a given name and given value
        Parameters:
        constantName - the constant name
        constantValue - the constant value

      • Constant

        public Constant​(java.lang.String constantName,
                double constantValue,
                java.lang.String description)
        Constructor - creates constant with a given name and given value. Additionally, description is being set.
        Parameters:
        constantName - the constant name
        constantValue - the constant value
        description - the constant description

      • Constant

        public Constant​(java.lang.String constantDefinitionString,
                PrimitiveElement... elements)
        Constructor for function definition in natural math language, for instance providing on string "f(x,y) = sin(x) + cos(x)" is enough to define function "f" with parameters "x and y" and function body "sin(x) + cos(x)".
        Parameters:
        constantDefinitionString - Constant definition in the form of one String, ie "c = 2" or "c = 2*sin(pi/3)"
        elements - Optional parameters (comma separated) such as Arguments, Constants, Functions

      • Constant

        private Constant​(Constant constantToClone)

    • Method Detail

      • buildErrorMessageInvalidConstantName

        private static java.lang.String buildErrorMessageInvalidConstantName​(java.lang.String constantName)

      • buildErrorMessageInvalidConstantDefinitionString

        private static java.lang.String buildErrorMessageInvalidConstantDefinitionString​(java.lang.String constantDefinitionString)

      • registerNoSyntaxErrorInDefinition

        private void registerNoSyntaxErrorInDefinition()

      • registerSyntaxErrorInDefinition

        private void registerSyntaxErrorInDefinition​(java.lang.String errorMessage)

      • getConstantName

        public java.lang.String getConstantName()
        Gets constant name
        Returns:
        the constant name as string.

      • setConstantName

        public void setConstantName​(java.lang.String constantName)
        Sets constant name. If constant is associated with any expression then this operation will set modified flag to each related expression.
        Parameters:
        constantName - the constant name

      • setConstantValue

        public void setConstantValue​(double constantValue)
        Sets constant value
        Parameters:
        constantValue - constant value

      • getConstantValue

        public double getConstantValue()
        Gets constant value.
        Returns:
        constant value as double

      • getDescription

        public java.lang.String getDescription()
        Gets constant description.
        Returns:
        constant description as string.

      • setDescription

        public void setDescription​(java.lang.String description)
        Sets constant description.
        Parameters:
        description - the constant description

      • getErrorMessage

        public java.lang.String getErrorMessage()
        Method return error message after
        Returns:
        Error message as string.

      • getSyntaxStatus

        public boolean getSyntaxStatus()
        Gets syntax status of the expression.
        Returns:
        Constant.NO_SYNTAX_ERRORS if there are no syntax errors, Const.SYNTAX_ERROR when syntax error was found or syntax status is unknown

      • addRelatedExpression

        void addRelatedExpression​(Expression expression)
        Adds related expression.
        Parameters:
        expression - the related expression.

      • removeRelatedExpression

        void removeRelatedExpression​(Expression expression)
        Removes related expression.
        Parameters:
        expression - the related expression.

      • setExpressionModifiedFlags

        void setExpressionModifiedFlags()
        Sets expression modified flag to each related expression.

      • cloneForThreadSafeInternal

        Constant cloneForThreadSafeInternal​(CloneCache cloneCache)

      • cloneForThreadSafeInternal

        Constant cloneForThreadSafeInternal​(Expression relatedExpressionThatInitiatedClone,
                                    CloneCache cloneCache)

      • cloneForThreadSafe

        public Constant cloneForThreadSafe()
        Creates a completely independent 1-1 clone that can be safely used by a separate thread. If the cloned element contains references to other elements (e.g. arguments, functions, constants), then they will also be cloned and the newly created element will contain references to the corresponding clones. Important - the API allows you to extract all these clones.
        Returns:
        Cloned object.