org.expasy.jpl.commons.base.math
Class MixedRadixNtupleFactory

java.lang.Object
  org.expasy.jpl.commons.base.math.MixedRadixNtupleFactory

All Implemented Interfaces:

org.apache.commons.collections15.Transformer<int[],List<int[]>>

public final class MixedRadixNtupleFactory
extends Object
implements org.apache.commons.collections15.Transformer<int[],List<int[]>>

This class generates generalized n-tuples.

Version:

1.0

Author:

nikitin

Nested Class Summary

static class

MixedRadixNtupleFactory.BadRadixException

Method Summary

static long	computeTupleNumber(int[] radices) Compute the number of all the t-uples given the radices.
static int[]	convertDecimal2Tuple(int code, int radix) Convert decimal to t-uple of given radix.
static int[]	convertDecimal2Tuple(int radix, int code, int size) Convert decimal to t-uple of given radix.
static int[]	convertString2Tuple(String tuple) Convert string to t-uple.
static int	convertTuple2Decimal(int[] tuple, int radix) Convert a tuple from radix to radix 10 (decimal).
static MixedRadixNtupleFactory	newInstance() Generate all tuples considering the given strict limits (excluded).
static MixedRadixNtupleFactory	newInstance(int limit)
static String	toString(List<int[]> ntuples) A simple string converter for n-tuples.
List<int[]>	transform(int[] radices) This algorithm generate all n-tuples where each ai have different upper limit li.
List<int[]>	transform(int n, int radix) This algorithm generate all n-tuples with same radix for any positions.

Methods inherited from class java.lang.Object

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

Method Detail

newInstance

public static MixedRadixNtupleFactory newInstance()

Generate all tuples considering the given strict limits (excluded).

Returns:

the list of tuples from [0, ..., 0] to [l0-1, ..., ln-1]

newInstance

public static MixedRadixNtupleFactory newInstance(int limit)

computeTupleNumber

public static long computeTupleNumber(int[] radices)

Compute the number of all the t-uples given the radices.

Parameters:

radices - the radices by position.

Returns:

the total number of t-uples.

convertTuple2Decimal

public static int convertTuple2Decimal(int[] tuple,
                                       int radix)
                                throws MixedRadixNtupleFactory.BadRadixException

Convert a tuple from radix to radix 10 (decimal).

Parameters:

radix - the fixed radix (max Character.MAX_RADIX).

tuple - the tuple to compute the code from.

Returns:

the code for the given tuple.

Throws:

MixedRadixNtupleFactory.BadRadixException - if radix is > Character.MAX_RADIX.

convertDecimal2Tuple

public static int[] convertDecimal2Tuple(int code,
                                         int radix)
                                  throws MixedRadixNtupleFactory.BadRadixException

Convert decimal to t-uple of given radix.

Parameters:

radix - the fixed radix (max 36)

code - the code to compute the tuple from

Returns:

the tuple for the given code

Throws:

MixedRadixNtupleFactory.BadRadixException - if radix > 36

convertDecimal2Tuple

public static int[] convertDecimal2Tuple(int radix,
                                         int code,
                                         int size)
                                  throws MixedRadixNtupleFactory.BadRadixException

Convert decimal to t-uple of given radix.

Parameters:

radix - the fixed radix (max 36)

code - the code to compute the tuple from

size - the size of the returned tuple rq: if size > tuple then add '0' else truncate.

Returns:

the tuple for the given code

Throws:

MixedRadixNtupleFactory.BadRadixException - if radix > 36

convertString2Tuple

public static int[] convertString2Tuple(String tuple)

Convert string to t-uple.

Parameters:

tuple - the string to convert.

Returns:

a t-uple.

transform

public List<int[]> transform(int n,
                             int radix)

This algorithm generate all n-tuples with same radix for any positions.

Parameters:

n - the number of digits.

radix - the radix for each digit.

Returns:

t-uples.

transform

public List<int[]> transform(int[] radices)

This algorithm generate all n-tuples where each ai have different upper limit li. [from knuth the AOCP, section 7.1.1 : Algorithm M]

Specified by:

transform in interface org.apache.commons.collections15.Transformer<int[],List<int[]>>

Parameters:

radices - the limits [l0, ..., ln] such as ai in [0, li[.

Returns:

t-uples.

toString

public static String toString(List<int[]> ntuples)

A simple string converter for n-tuples.

Parameters:

ntuples - the n-tuples to convert.

Returns:

a string representation of n-tuples.