Function
Class XMLFourierPolynomial

java.lang.Object
  Function.Function
      Function.DirectProdFunction
          Function.XMLFourierPolynomial

public class XMLFourierPolynomial
extends DirectProdFunction

An implementation of the abstract class Function used by class SFT, which defines a Function object by a given XML file that contains description of functions over G -> C , where G is the Cartesian product of Z_Ni. The representation is kept by storing elements in G and their function-coefficients.

The XML format should be as following:

• <functions>: the opening tag, must have a runid attribute with the value random for the function to be chosen randomly from a list of functions each time an element's ƒ-value is calculated, or an integer id of a function in the list of functions ahead.
  examples: <functions runid="random">, <functions runid="2">
• <function>: the opening tag of a function description. Must have an id attribute with some positive integer value (1, 2, ...).
  example: <function id="3">
• <term>: opening tag of a term (representing (a + bi)⋅χ_α1,...,αk(x₁,...,x₁k)). Has no attributes.
• <reCoeff>: opening tag of the real coefficient of the term (a in the example above). The text in it should be some double.
  example: <reCoeff>19.58</reCoeff>
• <imCoeff>: opening tag of the imaginary coefficient of the term (b in the example above). The text in it should be some double.
• <alpha>: opening tag of the element of the term (the vector of αs in the example above). The element in G, that is vector in Z_N1 x ... x Z_Nk, is represented by coord tags inside it.
  
• <coord>: opening tag of a coordinate in the element of the current term. Must have a index attribute with an integer value in 0,...,k-1. The text in it should be some element in Z_Ni, corresponding to the index attribute. All indices should have a value.

Author:

Elizabeth Firman and Ariel Stolerman

Constructor Summary

XMLFourierPolynomial(java.io.File XMLInputFile, long[] G)
Constructs a XMLFunction object from an input XML file as described in the class documentation.

Method Summary

java.util.Map<java.lang.String,FourierPolynomial>	getPolynomials()
Complex	getValue(long[] elem) Returns the value of the function for the input element in G.
boolean	isRandom() Specifies weather this XMLFunction object is "random" as described in the class documentation.
void	setG(long[] G) Sets G to a new value.

Methods inherited from class Function.DirectProdFunction

calcEuclideanNorm, calcInfinityNorm, getG

Methods inherited from class java.lang.Object

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

Constructor Detail

XMLFourierPolynomial

public XMLFourierPolynomial(java.io.File XMLInputFile,
                            long[] G)
                     throws FunctionException

Constructs a XMLFunction object from an input XML file as described in the class documentation.

Parameters:

XMLInputFile - The input XML file.

G - The vector of values describing G, i.e. Cartesian product of Z_Ni.

Throws:

FunctionException - If an XML parsing error occurred, I/O exception or invalid input.

Method Detail

getValue

public Complex getValue(long[] elem)

Returns the value of the function for the input element in G. If the Function is defined as random, a polynomial will randomly be selected from the list of Fourier polynomials and its value for the input element will be returned. Otherwise, the sole polynomial defined in the input XML file's value for the input element will be returned.

Specified by:

getValue in class DirectProdFunction

Parameters:

elem - The element whose this function's value is calculated.

Returns:

The value of the function for the input element in G.

isRandom

public boolean isRandom()

Specifies weather this XMLFunction object is "random" as described in the class documentation. That is, is value calculation performed randomly over all the polynomials given in the input XML file or only a specific polynomial is specified.

Returns:

True if and only if the value calculation mode is random over all the polynomials in the input XML file.

setG

public void setG(long[] G)
          throws FunctionException

Description copied from class: DirectProdFunction

Sets G to a new value.

Overrides:

setG in class DirectProdFunction

Parameters:

G - The vector of values describing G, the domain of the function

Throws:

FunctionException - If the one of the given values is less than or equals to 0.

getPolynomials

public java.util.Map<java.lang.String,FourierPolynomial> getPolynomials()