org.lsmp.djep.vectorJep.function

Class Determinant

java.lang.Object

org.nfunk.jep.function.PostfixMathCommand

org.lsmp.djep.vectorJep.function.Determinant

All Implemented Interfaces:

UnaryOperatorI, PostfixMathCommandI

public class Determinant
extends PostfixMathCommand
implements UnaryOperatorI

Calculate the Determinant of a matrix det([[1,2],[3,4]]) -> 1*4-2*3 = -2

Author:

Rich Morris Created on 13-Feb-2005

Field Summary

Fields inherited from class org.nfunk.jep.function.PostfixMathCommand

curNumberOfParameters, numberOfParameters

Constructor Summary

Constructors

Constructor and Description
Determinant()

Method Summary

Modifier and Type	Method and Description
Dimensions	calcDim(Dimensions ldim) Find the dimensions of this operator when applied to arguments with given dimensions.
MatrixValueI	calcValue(MatrixValueI res, MatrixValueI lhs) Calculates the value of this operator for given input with results stored in res.
Object	det(Object[][] mat) Calculates the determinant of an array Uses the fact that | a b c | | d e f | = a | e f | - b | d f | + c | d e | | g h i | | h i | | g i | | g i |
static Object[][]	dropRowCol(Object[][] mat, int xrow, int xcol) returns a matrix excluding the specifyed row and column
void	run(Stack s) Throws an exception because this method should never be called under normal circumstances.

Methods inherited from class org.nfunk.jep.function.PostfixMathCommand

checkNumberOfParameters, checkStack, getNumberOfParameters, setCurNumberOfParameters

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.nfunk.jep.function.PostfixMathCommandI

checkNumberOfParameters, getNumberOfParameters, setCurNumberOfParameters

Constructor Detail

Determinant

public Determinant()

Method Detail

calcDim

public Dimensions calcDim(Dimensions ldim)

Description copied from interface: UnaryOperatorI

Find the dimensions of this operator when applied to arguments with given dimensions.

Specified by:

calcDim in interface UnaryOperatorI

calcValue

public MatrixValueI calcValue(MatrixValueI res,
                              MatrixValueI lhs)
                       throws ParseException

Description copied from interface: UnaryOperatorI

Calculates the value of this operator for given input with results stored in res. res is returned. Using this method is slightly faster than the standard run method as it eliminates the construction of tempoary objects.

Specified by:

calcValue in interface UnaryOperatorI

Throws:

ParseException

dropRowCol

public static Object[][] dropRowCol(Object[][] mat,
                                    int xrow,
                                    int xcol)

returns a matrix excluding the specifyed row and column

det

public Object det(Object[][] mat)
           throws ParseException

Calculates the determinant of an array Uses the fact that | a b c | | d e f | = a | e f | - b | d f | + c | d e | | g h i | | h i | | g i | | g i |

Throws:

ParseException

run

public void run(Stack s)
         throws ParseException

Description copied from class: PostfixMathCommand

Throws an exception because this method should never be called under normal circumstances. Each function should use it's own run() method for evaluating the function. This includes popping off the parameters from the stack, and pushing the result back on the stack.

Specified by:

run in interface PostfixMathCommandI

Overrides:

run in class PostfixMathCommand

Throws:

ParseException