edu.neu.ccs.evergreen.ir
Interface RelationI

All Known Implementing Classes:

Relation

public interface RelationI

SOURCE

static final int SOURCE

See Also:

Constant Field Values

TARGET

static final int TARGET

See Also:

Constant Field Values

getRelationNumber

int getRelationNumber()

Returns:

an integer representing the relation number

setRelationNumber

void setRelationNumber(int relationNumber)

                       throws java.lang.IllegalArgumentException

Parameters:

relationNumber -

Throws:

java.lang.IllegalArgumentException - Thrwon if the relation number is invalid according to the rank

getRank

int getRank()

Returns:

rank of the relation

setRank

void setRank(int rank)

             throws java.lang.IllegalArgumentException

Currently unsupported Usually converting to a higher rank is simple. however converting to a lower rank might require the introduction of auxiliary variables and more than one relation might result from the operation

Parameters:

rank - sets the rank of the relation

Throws:

java.lang.IllegalArgumentException

getMagicNumber

int getMagicNumber(int variablePosition,

                   int value)

                   throws java.lang.IllegalArgumentException

Returns a magic number associated with a certain truth table column and value The magic number associated with column number 0 of the truth table and value 0 is basically a sequence of alternating 0 and 1 bits, packed together in one integer. The magic number associated with column number 0 of the truth table and value 1 is a sequence of alternating 1 and 0 bits, packed together in one integer. In general: (getMagicNumber(n,0) == ~getMagicNumber(n,1)) For column 1: magic numbers are fromed from sequences of two 0's followed by two 1's For column 2: magic numbers are formed from sequences of four 0's followed by four 1's For column 3: magic numbers are formed from sequeneces of eight 0's followed by eight 1's For column 4:magic numbers are formed from sequeneces of sixteen 0's followed by sixteen 1's There is no other possible columns as long as we are using 32 bit integers The lenght of the magic number depends on the internally stored relation rank

Parameters:

variablePosition - the position of the desired magic number

value - the value associated with the desired magic number

Returns:

Throws:

java.lang.IllegalArgumentException

getMask

int getMask()

Returns:

An integer with all of its bits set to 1. The length of the integer depends on the internally stored rank. 

the result is: 2^2^rank-1

Note: the method takes care of the case where 2^2^n is outside the integer range but 2^2^n-1 is not.

isIrrelevant

boolean isIrrelevant(int variablePosition)

                     throws java.lang.IllegalArgumentException

Checks if the variable at a given position is irrelevant to the internally stored relation

Parameters:

variablePosition - the variable to be checked

Returns:

true if the variable at vairablePosition is irrelevant otherwise returns false

Throws:

java.lang.IllegalArgumentException

numberOfRelevantVariables

int numberOfRelevantVariables()

Counts the number of relevantVariables in the relation

Returns:

The number of relevant variables in the relation

isForced

int isForced(int variablePosition)

             throws java.lang.IllegalArgumentException

Checks if the relation forces the given variablePosition

Parameters:

variablePosition - positon of the varible checked for being forced

Returns:

0 if the given relation forces the given variable to 0 1 if the given relation forces the given variable to 1 -1 given relation doesn't forces the given variable

Throws:

java.lang.IllegalArgumentException

firstForcedVariable

int firstForcedVariable(int startPosition)

                        throws java.lang.IllegalArgumentException

starting at the given startPosition, get the position of the first variable forced by the relation.

Parameters:

startPosition -

Returns:

-1 if nothing is forced the position of the first forced variable

Throws:

java.lang.IllegalArgumentException

nMap

int nMap(int variablePosition)

         throws java.lang.IllegalArgumentException

NMaps one of the variables in a relation i.e. replaces it by it's complement for example: nMapping x in Or(x,y,z) results in: or(!x,y,z)

Parameters:

relationNumber -

rank - rank of the given relation

variablePosition - the variable to be nmapped

Returns:

The number of the given relation with the specified variable nmapped

Throws:

java.lang.IllegalArgumentException

reduce

int reduce(int variablePosition,

           int value)

           throws java.lang.IllegalArgumentException

Reduces a relation by assigning a value to one of its variables

Parameters:

relationNumber -

rank -

variablePosition -

value -

Returns:

Throws:

java.lang.IllegalArgumentException

swap

int swap(int variablePosition1,

         int variablePosition2)

         throws java.lang.IllegalArgumentException

Throws:

java.lang.IllegalArgumentException

renme

int renme(int permutationSemantics,

          int... permutation)

          throws java.lang.IllegalArgumentException

Parameters:

relationNumber -

rank -

permutation -

Returns:

Throws:

java.lang.IllegalArgumentException

ones

int ones()

returns the number of ones in the given relationNumber

Parameters:

relationNumber -

rank -

Returns:

q

int q(int s)

      throws java.lang.IllegalArgumentException

Parameters:

s -

Returns:

the number of rows in the truth table with s 1's

Throws:

java.lang.IllegalArgumentException