Package com.singularsys.jep.walkers

Class TreeAnalyzer

java.lang.Object

com.singularsys.jep.walkers.PostfixTreeWalker

com.singularsys.jep.walkers.TreeAnalyzer

public class TreeAnalyzer
extends PostfixTreeWalker

Analyze an expression, counting the number of nodes of each type, and recording which variables, functions and operators occurred in the expression.

Constructor Summary

Constructors

Constructor	Description
TreeAnalyzer()	Creates an empty tree analyser.
TreeAnalyzer(Node node)	Create a new instance and Analyze the node.

Method Summary

Modifier and Type	Method	Description
void	analyze(Node node)	Analyze a node, results will be added to the current total.
Map<Object,Integer>	getConstants()	A map with each constant and the number of times it occurs
Map<String,Integer>	getFunctions()	A map with each function used and the number of times it occurred
int	getMaxDepth()	The depth of the tree
int	getNumConst()
int	getNumFunctions()
int	getNumNodes()
int	getNumOperators()
int	getNumUniqueVariables()
int	getNumVariables()
Map<Operator,Integer>	getOperators()	A map with each operator used and the number of times it occurred
String[]	getVariableNames()	Return the names of the variables, sorted alphabetically.
Map<Variable,Integer>	getVariables()	A map with each variable used and the number of times it occurred
void	merge(TreeAnalyzer ta)	Merge the result with the argument, producing total for all trees.
String	summary()	A short summary string
String	toString()	Reports statistics about the tree, number of nodes, depth, and the number of variables, functions, operators and constants with the number of times each occurs.
protected void	visit(ASTConstant node, int nchildren, int depth)	Visit a constant node
protected void	visit(ASTFunNode node, int nchildren, int depth)	Visit a function node
protected void	visit(ASTOpNode node, int nchildren, int depth)	Visit an operator node
protected void	visit(ASTVarNode node, int nchildren, int depth)	Visit a variable node

Methods inherited from class com.singularsys.jep.walkers.PostfixTreeWalker

suppressExaminingChildren, walk, walkSubEquations

Methods inherited from class java.lang.Object

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

Constructor Details

TreeAnalyzer

public TreeAnalyzer(Node node)
             throws JepException

Create a new instance and Analyze the node.

Parameters:

node - node to analyze

Throws:

JepException

TreeAnalyzer

public TreeAnalyzer()

Creates an empty tree analyser. Useful for producing combined statistics via the merge(TreeAnalyzer) method.

Method Details

analyze

public void analyze(Node node)
             throws JepException

Analyze a node, results will be added to the current total.

Parameters:

node -

Throws:

JepException

toString

public String toString()

Reports statistics about the tree, number of nodes, depth, and the number of variables, functions, operators and constants with the number of times each occurs.

Overrides:

toString in class Object

summary

public String summary()

A short summary string

Returns:

a one line summary

visit

protected void visit(ASTFunNode node,
 int nchildren,
 int depth)

Description copied from class: PostfixTreeWalker

Visit a function node

Specified by:

visit in class PostfixTreeWalker

Parameters:

node - the current node being visited

nchildren - number of children of the node

depth - depth of tree, root node is depth 1.

visit

protected void visit(ASTOpNode node,
 int nchildren,
 int depth)

Description copied from class: PostfixTreeWalker

Visit an operator node

Specified by:

visit in class PostfixTreeWalker

Parameters:

node - the current node being visited

nchildren - number of children of the node

depth - depth of tree, root node is depth 1.

visit

protected void visit(ASTVarNode node,
 int nchildren,
 int depth)

Description copied from class: PostfixTreeWalker

Visit a variable node

Specified by:

visit in class PostfixTreeWalker

Parameters:

node - the current node being visited

nchildren - number of children of the node

depth - depth of tree, root node is depth 1.

visit

protected void visit(ASTConstant node,
 int nchildren,
 int depth)

Description copied from class: PostfixTreeWalker

Visit a constant node

Specified by:

visit in class PostfixTreeWalker

Parameters:

node - the current node being visited

nchildren - number of children of the node

depth - depth of tree, root node is depth 1.

getMaxDepth

public int getMaxDepth()

The depth of the tree

Returns:

depth, depth of root node is 1

getNumConst

public int getNumConst()

getNumFunctions

public int getNumFunctions()

getNumNodes

public int getNumNodes()

getNumOperators

public int getNumOperators()

getNumVariables

public int getNumVariables()

getNumUniqueVariables

public int getNumUniqueVariables()

getOperators

public Map<Operator,Integer> getOperators()

A map with each operator used and the number of times it occurred

Returns:

a map whose keys are the operators and the values are the number of occurrences

getVariables

public Map<Variable,Integer> getVariables()

A map with each variable used and the number of times it occurred

Returns:

a map whose keys are the variables and the values are the number of occurrences

getVariableNames

public String[] getVariableNames()

Return the names of the variables, sorted alphabetically.

Returns:

an array of variable names

getFunctions

public Map<String,Integer> getFunctions()

A map with each function used and the number of times it occurred

getConstants

public Map<Object,Integer> getConstants()

A map with each constant and the number of times it occurs

merge

public void merge(TreeAnalyzer ta)

Merge the result with the argument, producing total for all trees.

Parameters:

ta -