Package com.singularsys.extensions.xjep

Class TreeUtils

  • All Implemented Interfaces:
    JepComponent, java.io.Serializable
    Direct Known Subclasses:
    FieldTreeUtils
    public class TreeUtils
extends java.lang.Object
implements JepComponent
    A set of Utility functions for working with Jep expression trees. Main methods are
    • isConstant test if its a constant. Many other is... methods.
    Author:
    rich
    See Also:
    Serialized Form

    • Constructor Summary

      Constructors 
      Modifier Constructor Description
        TreeUtils()
      Constructor when used as a Jep component.
        TreeUtils​(NumberFactory nf)
      Stand alone constructor with supplied NumberFactory
      protected TreeUtils​(java.lang.Object zero, java.lang.Object one, java.lang.Object minus_one, java.lang.Object two, java.lang.Object pinf, java.lang.Object ninf, java.lang.Object nan)  

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      Complex complexValue​(java.lang.Object val)  
      static Node[] getChildrenAsArray​(Node node)
      returns the children of a node as an array of nodes.
      java.lang.Object getCI()
      Complex imaginary unit
      java.lang.Object getCMinusI()
      Complex minus i
      java.lang.Object getCMinusOne()
      Complex minus one
      java.lang.Object getCOne()
      Complex one
      java.lang.Object getCZero()
      Complex zero
      java.lang.Object getFalse()
      The value used to represent a False ASTconstant value.
      int getIntValue​(java.lang.Object val)
      Value of an ASTConstant node cast to an Integer should only be used if isIntegerVal(Object) returns true.
      JepComponent getLightWeightInstance()
      Gets a light-weight instance suitable for using in multiple threads.
      java.lang.Object getMinusOne()
      Number representing -1
      java.lang.Object getNAN()
      Number representing NaN
      java.lang.Object getNegativeInfinity()
      Number representing +Infty
      java.lang.Object getOne()
      Number representing one
      java.lang.Object getPositiveInfinity()
      Number representing +Infty
      java.lang.Object getTrue()
      The value used to represent a True ASTconstant value.
      java.lang.Object getTwo()
      Number representing two
      java.lang.Object getZero()
      Number representing zero
      boolean hasInfinity()
      Whether we have a working value for +/- Infinity
      boolean hasNaN()
      Whether we have a working value for NaN
      void init​(Jep jep)
      Initialize the component.
      int intValue​(Node node)
      Value of an ASTConstant node cast to an Integer should only be used if isInteger returns true.
      boolean isBinaryOperator​(Node node)
      Returns true if node represents a binary operator
      boolean isComplex​(Node node)
      returns true if node is an ASTConstant of type Complex
      boolean isComplexVal​(java.lang.Object val)
      Test a value for being complex.
      boolean isConstant​(Node node)
      returns true if node is an ASTConstant
      boolean isConstantVariable​(Node node)
      returns true if node is an ASTVarNode with a constant variable
      boolean isFunction​(Node node)
      returns true if node is an ASTFunNode
      boolean isInfinity​(Node node)
      returns true if node is a ASTConstant with a Infinite component TODO do proper treatment of signed infinity
      boolean isInfinityVal​(java.lang.Object val)
      Test a value for being infinite.
      boolean isInteger​(Node node)
      return true is the node is an ASTConstant with a value which is integral like 1.0.
      boolean isIntegerVal​(java.lang.Object val)
      Test a value for being an integer.
      boolean isMinusOne​(Node node)
      returns true if node is a ASTConstant with value Double(-1) or Complex(-1,0)
      boolean isMinusOneVal​(java.lang.Object val)
      Test a value for being minus one.
      boolean isNaN​(Node node)
      returns true if node is a ASTConstant with a NaN component
      boolean isNaNVal​(java.lang.Object val)
      Test a value for being NaN.
      boolean isNegative​(Node node)
      returns true if node is an ASTConstant with a negative value isNegativeVal(Object)
      boolean isNegativeVal​(java.lang.Object val)
      Test a value for being negative.
      boolean isOne​(Node node)
      returns true if node is a ASTConstant with value Double(1) or Complex(1,0)
      boolean isOneVal​(java.lang.Object val)
      Test a value for being one.
      boolean isOperator​(Node node)
      returns true if node is an ASTOpNode
      boolean isPositive​(Node node)
      returns true if node is an ASTConstant with a positive Number value
      boolean isPositiveVal​(java.lang.Object val)
      Test a value for being positive.
      boolean isReal​(Node node)
      returns true if node is a ASTConstant with Number value
      boolean isRealVal​(java.lang.Object val)  
      boolean isUnaryOperator​(Node node)
      Returns true if node represents a unary operator
      boolean isVariable​(Node node)
      returns true if node is an ASTVarNode
      boolean isZero​(Node node)
      returns true if node is a ASTConstant with value Double(0) or Complex(0,0)
      boolean isZeroVal​(java.lang.Object val)
      Test a value for being zero.
      static Node setChildrenIfNeeded​(Node node, Node[] children)
      Sets the children of a node if they have changed for it current children.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Constructor Detail

      • TreeUtils

        public TreeUtils​(NumberFactory nf)
        Stand alone constructor with supplied NumberFactory
        Parameters:
        nf -

      • TreeUtils

        public TreeUtils()
        Constructor when used as a Jep component. The NumberFactory is set using the init(Jep) method

      • TreeUtils

        protected TreeUtils​(java.lang.Object zero,
                    java.lang.Object one,
                    java.lang.Object minus_one,
                    java.lang.Object two,
                    java.lang.Object pinf,
                    java.lang.Object ninf,
                    java.lang.Object nan)

    • Method Detail

      • isReal

        public boolean isReal​(Node node)
        returns true if node is a ASTConstant with Number value

      • isRealVal

        public boolean isRealVal​(java.lang.Object val)

      • isZero

        public boolean isZero​(Node node)
        returns true if node is a ASTConstant with value Double(0) or Complex(0,0)

      • isZeroVal

        public boolean isZeroVal​(java.lang.Object val)
        Test a value for being zero. This implementation test for Double 0 using ==, or Complex 0.
        Parameters:
        val - value to test
        Returns:
        true in value is zero false otherwise

      • isOne

        public boolean isOne​(Node node)
        returns true if node is a ASTConstant with value Double(1) or Complex(1,0)

      • isOneVal

        public boolean isOneVal​(java.lang.Object val)
        Test a value for being one. This implementation test for Double 1 or Complex 1.
        Parameters:
        val - value to test
        Returns:
        true in value is one false otherwise

      • isMinusOne

        public boolean isMinusOne​(Node node)
        returns true if node is a ASTConstant with value Double(-1) or Complex(-1,0)

      • isMinusOneVal

        public boolean isMinusOneVal​(java.lang.Object val)
        Test a value for being minus one. This implementation test for Double -1 or Complex -1.
        Parameters:
        val - value to test
        Returns:
        true in value is -1 false otherwise

      • isInfinity

        public boolean isInfinity​(Node node)
        returns true if node is a ASTConstant with a Infinite component TODO do proper treatment of signed infinity

      • isInfinityVal

        public boolean isInfinityVal​(java.lang.Object val)
        Test a value for being infinite. This implementation test for Double infinite or Complex infinite
        Parameters:
        val - value to test
        Returns:
        true in value is infinite false otherwise

      • isNaN

        public boolean isNaN​(Node node)
        returns true if node is a ASTConstant with a NaN component

      • isNaNVal

        public boolean isNaNVal​(java.lang.Object val)
        Test a value for being NaN. This implementation test for Double NaN or Complex NaN.
        Parameters:
        val - value to test
        Returns:
        true in value is zero false otherwise

      • isNegative

        public boolean isNegative​(Node node)
        returns true if node is an ASTConstant with a negative value isNegativeVal(Object)

      • isNegativeVal

        public boolean isNegativeVal​(java.lang.Object val)
        Test a value for being negative. This implementation test for Numbers. Complex values of the form (x + i0) with x<0 are considered negative
        Parameters:
        val - value to test
        Returns:
        true in value is negative false otherwise

      • isPositive

        public boolean isPositive​(Node node)
        returns true if node is an ASTConstant with a positive Number value

      • isPositiveVal

        public boolean isPositiveVal​(java.lang.Object val)
        Test a value for being positive. This implementation test for Numbers. Complex numbers of the form (x + i0) where x>0 are considered positive.
        Parameters:
        val - value to test
        Returns:
        true in value is positive false otherwise

      • isComplex

        public boolean isComplex​(Node node)
        returns true if node is an ASTConstant of type Complex

      • isComplexVal

        public boolean isComplexVal​(java.lang.Object val)
        Test a value for being complex. This implementation test for value being of type Complex.
        Parameters:
        val - value to test
        Returns:
        true in value is positive false otherwise

      • isInteger

        public boolean isInteger​(Node node)
        return true is the node is an ASTConstant with a value which is integral like 1.0.

      • isIntegerVal

        public boolean isIntegerVal​(java.lang.Object val)
        Test a value for being an integer. This implementation test for Numbers whose double value and int value are equal. Complex values of the form (n + i 0) are considered to be integers.
        Parameters:
        val - value to test
        Returns:
        true in value is positive false otherwise

      • intValue

        public int intValue​(Node node)
             throws EvaluationException
        Value of an ASTConstant node cast to an Integer should only be used if isInteger returns true.
        Parameters:
        node -
        Returns:
        an integer value identical to the nodes constant
        Throws:
        EvaluationException - if the number cannot be converted exactly to an integer

      • getTrue

        public java.lang.Object getTrue()
        The value used to represent a True ASTconstant value.
        Returns:
        Boolean.True

      • getFalse

        public java.lang.Object getFalse()
        The value used to represent a False ASTconstant value.
        Returns:
        Boolean.False

      • isConstant

        public boolean isConstant​(Node node)
        returns true if node is an ASTConstant

      • isVariable

        public boolean isVariable​(Node node)
        returns true if node is an ASTVarNode

      • isConstantVariable

        public boolean isConstantVariable​(Node node)
        returns true if node is an ASTVarNode with a constant variable

      • isOperator

        public boolean isOperator​(Node node)
        returns true if node is an ASTOpNode

      • isBinaryOperator

        public boolean isBinaryOperator​(Node node)
        Returns true if node represents a binary operator

      • isUnaryOperator

        public boolean isUnaryOperator​(Node node)
        Returns true if node represents a unary operator

      • isFunction

        public boolean isFunction​(Node node)
        returns true if node is an ASTFunNode

      • setChildrenIfNeeded

        public static Node setChildrenIfNeeded​(Node node,
                                       Node[] children)
                                throws ParseException
        Sets the children of a node if they have changed for it current children.
        Throws:
        ParseException

      • getChildrenAsArray

        public static Node[] getChildrenAsArray​(Node node)
        returns the children of a node as an array of nodes.

      • getCI

        public java.lang.Object getCI()
        Complex imaginary unit
        Returns:
        Complex(0,1)

      • getCMinusI

        public java.lang.Object getCMinusI()
        Complex minus i
        Returns:
        Complex(0,-1)

      • getCMinusOne

        public java.lang.Object getCMinusOne()
        Complex minus one
        Returns:
        Complex(-1,0)

      • getCOne

        public java.lang.Object getCOne()
        Complex one
        Returns:
        Complex(1,0)

      • getCZero

        public java.lang.Object getCZero()
        Complex zero
        Returns:
        Complex(0,0)

      • getZero

        public java.lang.Object getZero()
        Number representing zero
        Returns:
        0.0d

      • getOne

        public java.lang.Object getOne()
        Number representing one
        Returns:
        1.0d

      • getMinusOne

        public java.lang.Object getMinusOne()
        Number representing -1
        Returns:
        -1.0d

      • getTwo

        public java.lang.Object getTwo()
        Number representing two
        Returns:
        2.0d

      • hasNaN

        public boolean hasNaN()
        Whether we have a working value for NaN
        Returns:

      • hasInfinity

        public boolean hasInfinity()
        Whether we have a working value for +/- Infinity
        Returns:

      • getNAN

        public java.lang.Object getNAN()
        Number representing NaN
        Returns:
        Double.NaN or null if hasNaN() returns false

      • getPositiveInfinity

        public java.lang.Object getPositiveInfinity()
        Number representing +Infty
        Returns:
        Double.POSITIVE_INFINITY or null if hasNaN() returns false

      • getNegativeInfinity

        public java.lang.Object getNegativeInfinity()
        Number representing +Infty
        Returns:
        Double.NEGATIVE_INFINITY or null if hasNaN() returns false

      • getLightWeightInstance

        public JepComponent getLightWeightInstance()
        Description copied from interface: JepComponent
        Gets a light-weight instance suitable for using in multiple threads.
        Specified by:
        getLightWeightInstance in interface JepComponent
        Returns:
        either an new instance, null or 'this'.

      • init

        public void init​(Jep jep)
        Description copied from interface: JepComponent
        Initialize the component. This methods is called whenever a component is added to Jep. Hence it allows components to keep track of the other components they may rely on.
        Specified by:
        init in interface JepComponent
        Parameters:
        jep - the current Jep instance