edu.psu.geovista.app.spreadsheet.functions
Class Function

java.lang.Object
  edu.psu.geovista.app.spreadsheet.functions.Function

Direct Known Subclasses:

FunctionAverage, FunctionCount, FunctionCustomize, FunctionMedian, FunctionSin, FunctionSP, FunctionSum

public abstract class Function

extends java.lang.Object

Field Summary

protected Formula

owner

Constructor Summary

Function()

Method Summary

protected static void	checkParamsExist(Node func)
abstract java.lang.Number	evaluate(Node node) This should be implemented in each function.
abstract java.lang.String	getDescription() Return the description of the function
protected Node	getFirst(Node param)
Formula	getOwner()
static SelectionRange	getRangeArea(Node node) Jin: Only for those function whose arguments is set of range.
protected float	getSingleParameter(Node node) This gets the first float number of a parameter list, for functions only accepting a single parameter such as ABS, COS , etc.
protected Function	getSupportFuntion(java.lang.String fname, Formula owner)
abstract java.lang.String	getUsage() Return the usage of the function
protected boolean	isRange(Node param)
static SelectionRange	processColonNode(Node colonNode) convert a colon node(which contain 2 ranges) into a SelectionRange
boolean	requireParams() Whether this function requires parameters.
void	setOwner(Formula owner)

Methods inherited from class java.lang.Object

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

Field Detail

owner

protected Formula owner

Constructor Detail

Function

public Function()

Method Detail

isRange

protected boolean isRange(Node param)

getFirst

protected Node getFirst(Node param)

checkParamsExist

protected static void checkParamsExist(Node func)
                                throws ParserException

Throws:

ParserException

getSingleParameter

protected float getSingleParameter(Node node)
                            throws ParserException,
                                   NoReferenceException

This gets the first float number of a parameter list, for functions only accepting a single parameter such as ABS, COS , etc.

Parameters:

node - the edu.psu.geovista.app.spreadsheet.formula unit

Returns:

the float number

Throws:

ParserException

NoReferenceException

evaluate

public abstract java.lang.Number evaluate(Node node)
                                   throws ParserException,
                                          NoReferenceException

This should be implemented in each function.

Parameters:

node - the function node starting with the funciton name with a chain of parameters

Throws:

ParserException

NoReferenceException

getUsage

public abstract java.lang.String getUsage()

Return the usage of the function

getDescription

public abstract java.lang.String getDescription()

Return the description of the function

requireParams

public boolean requireParams()

Whether this function requires parameters. By default yes.

See Also:

FunctionPI, FunctionE

getRangeArea

public static SelectionRange getRangeArea(Node node)
                                   throws ParserException

Jin: Only for those function whose arguments is set of range. e.g.: SUM, AVG,MEAN...

Parameters:

node - the function node.

Returns:

address(x,y) in view

Throws:

ParserException

processColonNode

public static SelectionRange processColonNode(Node colonNode)
                                       throws ParserException

convert a colon node(which contain 2 ranges) into a SelectionRange

Throws:

ParserException

getSupportFuntion

protected Function getSupportFuntion(java.lang.String fname,
                                     Formula owner)

setOwner

public void setOwner(Formula owner)

getOwner

public Formula getOwner()