Package com.singularsys.extensions.matrix

Class DimensionVisitor

java.lang.Object

com.singularsys.extensions.matrix.DimensionVisitor

All Implemented Interfaces:

GenericVisitor<Dimensions,DimensionVisitor.NodeChecker,ParseException>, JepComponent, Serializable

Direct Known Subclasses:

DDimensionVisitor

public class DimensionVisitor
extends Object
implements GenericVisitor<Dimensions,DimensionVisitor.NodeChecker,ParseException>, JepComponent

Annotates nodes with the dimension of the vector or matrix.

Warning messages are sometimes generated. This list can be accessed using getWarnings()

Since Jep 4.1, extension 2.2, this now implements GenericVisitor some method signatures have changed to be more specific.

See Also:

• Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	DimensionVisitor.NodeChecker	Class to check conditions on a node
static class	DimensionVisitor.VariableNodeChecker	Checks nodes to see if the variable matches one in the supplied list

Field Summary

Fields

Modifier and Type	Field	Description
static final Node.HookKey	DIM_KEY	A Key to use with Nodes and Variables to store the dimensions.
protected Jep	jep
protected OperatorTableI	ot

Constructor Summary

Constructors

Constructor	Description
DimensionVisitor()	Should only be used as when the init(Jep) will be called.
DimensionVisitor(Jep jep)	Standalone constructor with a supplied Jep instance

Method Summary

Modifier and Type	Method	Description
Dimensions	calcDims(Node node)
Dimensions	calcVariableDimensionsByValue(Variable var)	Calculate and sets the dimensions of a variable using its value
static Dimensions	getDimByValue(Object val)	Find the dimensions of a given value.
static Dimensions	getDimensions(Node node)	Get the dimensions of a node.
static Dimensions	getDimensions(Variable var)	Get the dimensions of a variable.
JepComponent	getLightWeightInstance()	Gets a light-weight instance suitable for using in multiple threads.
List<String>	getWarnings()	The list of warnings when a variable has changed dimension.
void	init(Jep jep1)	Initialize the component.
ParseException	makeException(String message)	Create an Exception of the correct type.
static void	setVariableDimensions(Variable var, Dimensions dim)	Sets the dimensions of a variable to give value.
Dimensions	visit(XVariable var)	If the variable has an equation visit that equation to find the dimensions and set the variables dimension.
Dimensions	visit(ASTConstant node, DimensionVisitor.NodeChecker data)	Visit a constant node
Dimensions	visit(ASTFunNode node, DimensionVisitor.NodeChecker data)	Visit a function node
Dimensions	visit(ASTOpNode node, DimensionVisitor.NodeChecker data)	Visit an operator node
Dimensions	visit(ASTVarNode node, DimensionVisitor.NodeChecker data)	Visit a variable node.
Dimensions	visit(Node node)	Annotate every node in the tree.
protected Dimensions	visitAssign(ASTOpNode node, Object data)	Visit an assignment operator.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.singularsys.jep.GenericVisitor

makeException, visit, visitChildren

Field Details

DIM_KEY

public static final Node.HookKey DIM_KEY

A Key to use with Nodes and Variables to store the dimensions.

jep

protected Jep jep

ot

protected OperatorTableI ot

Constructor Details

DimensionVisitor

public DimensionVisitor()

Should only be used as when the init(Jep) will be called.

DimensionVisitor

public DimensionVisitor(Jep jep)

Standalone constructor with a supplied Jep instance

Parameters:

jep - Jep instance

Method Details

calcDims

public Dimensions calcDims(Node node)
                    throws ParseException

Throws:

ParseException

getDimByValue

public static Dimensions getDimByValue(Object val)

Find the dimensions of a given value. Handles the cases when the value is of types MatrixI, VectorI, one and two-dimensional java.util.Vectors.

Parameters:

val - value

Returns:

dimensions of object, unknown types returns SCALAR.

setVariableDimensions

public static void setVariableDimensions(Variable var,
 Dimensions dim)

Sets the dimensions of a variable to give value. Can be used in a situation when a variable is defined without a value being set for example

     Variable var = jep.addVariable("v");
     dimensionVisitor.setVariableDimensions(var,Dimensions.THREE);
 

Parameters:

var -

dim -

Since:

Jep 4.0/Extensions 2.1

calcVariableDimensionsByValue

public Dimensions calcVariableDimensionsByValue(Variable var)

Calculate and sets the dimensions of a variable using its value

Parameters:

var - the variable, it is assumed it does not have a null value

Returns:

the dimensions of its value

Throws:

NullPointerException - if the variable does not have a value

visit

public Dimensions visit(XVariable var)
                 throws ParseException

If the variable has an equation visit that equation to find the dimensions and set the variables dimension.

Parameters:

var - the variable

Returns:

the calculated dimension

Throws:

ParseException - if the variable does not have an equation

Since:

Jep 4.0/Extensions 2.1

getDimensions

public static Dimensions getDimensions(Variable var)

Get the dimensions of a variable.

Parameters:

var - the variable

Returns:

the dimensions or null if it has not been set

Since:

Jep 4.0/Extensions 2.1

getDimensions

public static Dimensions getDimensions(Node node)

Get the dimensions of a node. For use in a static context use (Dimensions) node.getHook(DimensionVisitor.DIM_KEY);

Parameters:

node - the node

Returns:

the dimensions or null if it has not been previously calculated

Since:

Jep 4.0/Extensions 2.1

visit

public Dimensions visit(Node node)
                 throws ParseException

Annotate every node in the tree.

Parameters:

node - root node of the expression

Returns:

dimensions of the root node

Throws:

ParseException

visit

public Dimensions visit(ASTConstant node,
 DimensionVisitor.NodeChecker data)
                 throws ParseException

Description copied from interface: GenericVisitor

Visit a constant node

Specified by:

visit in interface GenericVisitor<Dimensions,DimensionVisitor.NodeChecker,ParseException>

Parameters:

node - current node

data - context data

Returns:

the result of visiting the node

Throws:

ParseException

visit

public Dimensions visit(ASTVarNode node,
 DimensionVisitor.NodeChecker data)
                 throws ParseException

Visit a variable node.

Specified by:

visit in interface GenericVisitor<Dimensions,DimensionVisitor.NodeChecker,ParseException>

Parameters:

node - the variable node

data - a DimensionVisitor.NodeChecker to check if the variable appears on the LHS of an assignment

Returns:

the dimensions of the variable

Throws:

ParseException - if the variable matches the LHS variable

visit

public Dimensions visit(ASTFunNode node,
 DimensionVisitor.NodeChecker data)
                 throws ParseException

Description copied from interface: GenericVisitor

Visit a function node

Specified by:

visit in interface GenericVisitor<Dimensions,DimensionVisitor.NodeChecker,ParseException>

Parameters:

node - current node

data - context data

Returns:

the result of visiting the node

Throws:

ParseException

visit

public Dimensions visit(ASTOpNode node,
 DimensionVisitor.NodeChecker data)
                 throws ParseException

Description copied from interface: GenericVisitor

Visit an operator node

Specified by:

visit in interface GenericVisitor<Dimensions,DimensionVisitor.NodeChecker,ParseException>

Parameters:

node - current node

data - context data

Returns:

the result of visiting the node

Throws:

ParseException

visitAssign

protected Dimensions visitAssign(ASTOpNode node,
 Object data)
                          throws ParseException

Visit an assignment operator. Will add the LHS variable to the DimensionVisitor.VariableNodeChecker. Sets the dimension of the LHS variable to the dimension of the RHS.

Parameters:

node - the node with an assignment operator

data - a DimensionVisitor.VariableNodeChecker to check if the variable appears on the LHS of an assignment

Returns:

dimensions of the RHS

Throws:

ParseException - in the LHS variable appears on the RHS

getWarnings

public List<String> getWarnings()

The list of warnings when a variable has changed dimension.

Returns:

init

public void init(Jep jep1)

Description copied from interface: JepComponent

Initialize the component. This method 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:

jep1 - the current Jep instance

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 a new instance, null or 'this'.

makeException

public ParseException makeException(String message)

Description copied from interface: GenericVisitor

Create an Exception of the correct type. A typical implementation is

@Override
public JepException makeException(String message) {
 return new JepException(message);
}

Specified by:

makeException in interface GenericVisitor<Dimensions,DimensionVisitor.NodeChecker,ParseException>

Parameters:

message - error message

Returns:

an Exception