org.lsmp.djep.matrixJep
Interface SpecialPreProcessorI

All Known Implementing Classes:

MAssign, MDiff, MList, MMap, MPower

public interface SpecialPreProcessorI

Applies a special preprocessing step for a function or operator.

Author:

Rich Morris Created on 14-Feb-2005

Method Summary

MatrixNodeI

preprocess(ASTFunNode node, MatrixPreprocessor visitor, MatrixJep jep, MatrixNodeFactory nf) Subverts the preprocessing stage.

Method Detail

preprocess

MatrixNodeI preprocess(ASTFunNode node,
                       MatrixPreprocessor visitor,
                       MatrixJep jep,
                       MatrixNodeFactory nf)
                       throws ParseException

Subverts the preprocessing stage. Preprocessing performs a number of operations:

1. Converts each node into one of the subtypes of MatrixNodeI
2. Calculate the dimensions for the results
3. Performs any special symbolic operations such as differentation

In general the first step in preprocessing is to run the preprocessor on the children of the node. This can be done using

 MatrixNodeI children[] = visitor.visitChildrenAsArray(node,null);
 

The final step is to construct a node of the correct type. The MatrixNodeFactory argument has a number of methods to do this. For example

 return (ASTMFunNode) nf.buildOperatorNode(node.getOperator(),children,rhsDim);
 

Note how the dimension is specified.

Parameters:

node - the top node of the tree representing the function and its arguments.

visitor - A reference to the preprocessing visitor.

jep - A reference of the MatrixJep instance.

nf - A reference to the node factory object.

Returns:

A new MatrixNodeI representing the converted function.

Throws:

ParseException - if some error occurs.