doc_summary_of_astnode_methods Class Reference

Detailed Description

There are a number of methods for interrogating the type of an ASTNode and for testing whether a node belongs to a general category of constructs. The methods on ASTNode for this purpose are the following:

• long ASTNode.getType() returns the type of this AST node.
• bool ASTNode.isConstant() returns True if this AST node is a MathML constant (True, False, pi, exponentiale), False otherwise.
• bool ASTNode.isBoolean() returns True if this AST node returns a Boolean value (by being either a logical operator, a relational operator, or the constant True or False).
• bool ASTNode.isFunction() returns True if this AST node is a function (i.e., a MathML defined function such as exp or else a function defined by a FunctionDefinition in the Model).
• bool ASTNode.isInfinity() returns True if this AST node is the special IEEE 754 value infinity.
• bool ASTNode.isInteger() returns True if this AST node is holding an integer value.
• bool ASTNode.isNumber() returns True if this AST node is holding any number.
• bool ASTNode.isLambda() returns True if this AST node is a MathML lambda construct.
• bool ASTNode.isLog10() returns True if this AST node represents the log10 function, specifically, that its type is AST_FUNCTION_LOG and it has two children, the first of which is an integer equal to 10.
• bool ASTNode.isLogical() returns True if this AST node is a logical operator (and, or, not, xor).
• bool ASTNode.isName() returns True if this AST node is a user-defined name or (in SBML Level 2) one of the two special csymbol constructs "delay" or "time".
• bool ASTNode.isNaN() returns True if this AST node has the special IEEE 754 value "not a number" (NaN).
• bool ASTNode.isNegInfinity() returns True if this AST node has the special IEEE 754 value of negative infinity.
• bool ASTNode.isOperator() returns True if this AST node is an operator (e.g., +, -, etc.)
• bool ASTNode.isPiecewise() returns True if this AST node is the MathML piecewise function.
• bool ASTNode.isRational() returns True if this AST node is a rational number having a numerator and a denominator.
• bool ASTNode.isReal() returns True if this AST node is a real number (specifically, AST_REAL_E or AST_RATIONAL).
• bool ASTNode.isRelational() returns True if this AST node is a relational operator.
• bool ASTNode.isSqrt() returns True if this AST node is the square-root operator
• bool ASTNode.isUMinus() returns True if this AST node is a unary minus.
• bool ASTNode.isUnknown() returns True if this AST node's type is unknown.

Programs manipulating AST node structures should check the type of a given node before calling methods that return a value from the node. The following are the ASTNode object methods available for returning values from nodes:

• long ASTNode.getInteger()
• char ASTNode.getCharacter()
• string ASTNode.getName()
• long ASTNode.getNumerator()
• long ASTNode.getDenominator()
• float ASTNode.getReal()
• float ASTNode.getMantissa()
• long ASTNode.getExponent()

Of course, all of this would be of little use if libSBML didn't also provide methods for setting the values of AST node objects! And it does. The methods are the following:

• ASTNode.setCharacter(char) sets the value of this ASTNode to the given character. If character is one of +, -, *, / or ^, the node type will be to the appropriate operator type. For all other characters, the node type will be set to AST_UNKNOWN
• ASTNode.setName(string) sets the value of this AST node to the given name. The node type will be set (to AST_NAME) only if the AST node was previously an operator (isOperator(node) != 0) or number (isNumber(node) != 0). This allows names to be set for AST_FUNCTIONs and the like.
• ASTNode.setValue(int) sets the value of the node to the given integer. Equivalent to the next method.
• ASTNode.setValue(long) sets the value of the node to the given integer.
• ASTNode.setValue(long, long) sets the value of this ASTNode to the given rational in two parts: the numerator and denominator. The node type is set to AST_RATIONAL.
• ASTNode.setValue(float) sets the value of this ASTNode to the given real (float) and sets the node type to AST_REAL.
• ASTNode.setValue(float, long) sets the value of this ASTNode to the given real (float) in two parts: the mantissa and the exponent. The node type is set to AST_REAL_E.

Finally, ASTNode also defines some miscellaneous methods for manipulating ASTs:

• ASTNode ASTNode(long) creates a new ASTNode object and returns a pointer to it. The returned node will have the type identified by the code passed as the argument, or a type of AST_UNKNOWN if no type is explicitly given or the type code is unrecognized.
• unsigned int ASTNode.getNumChildren() returns the number of children of this AST node or 0 is this node has no children.
• ASTNode.addChild(ASTNode) adds the given node as a child of this AST node. Child nodes are added in left-to-right order.
• ASTNode.prependChild(ASTNode) adds the given node as a child of this AST node. This method adds child nodes in right-to-left order.
• ASTNode ASTNode.getChild(unsigned int) returns the nth child of this AST node or NULL if this node has no nth child (n > (ASTNode.getNumChildren() - 1)).
• ASTNode ASTNode.getLeftChild() returns the left child of this AST node. This is equivalent to ASTNode.getChild();
• ASTNode ASTNode.getRightChild() returns the right child of this AST node or NULL if this node has no right child.
• ASTNode.swapChildren(ASTNode) swaps the children of this ASTNode with the children of that ASTNode.
• ASTNode.setType(long) sets the type of this ASTNode to the type identified by the type code passed as argument, or to AST_UNKNOWN if the type is unrecognized.