Java List Permutate permuteList(List in, int seed)

Description

permute List

License

Apache License

Declaration

public static <T> List<T> permuteList(List<T> in, int seed) 

Method Source Code

//package com.java2s;
/*//from   ww  w  .j ava  2 s .c o  m
 Copyright (C) 2012 The Stanford MobiSocial Laboratory
    
   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at
    
   http://www.apache.org/licenses/LICENSE-2.0
    
   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
*/

import java.util.*;

public class Main {
    public static <T> List<T> permuteList(List<T> in, int seed) {
        // create a copy of the input
        List<T> result = new ArrayList<T>();
        result.addAll(in);

        Random R = new Random(seed);
        for (int permuteSize = in.size(); permuteSize > 1; permuteSize--) {
            int pos = Math.abs(R.nextInt()) % permuteSize;
            // pos is in teh range 0..permuteSize-1
            // interchange elements permuteSize-1 and pos
            T tmp = result.get(permuteSize - 1);
            result.set(permuteSize - 1, result.get(pos));
            result.set(pos, tmp);
        }
        return result;
    }
}

Related

1. permute(List list1)
2. permute(List list, int index, List> result)
3. permute(T[] arr, List p)
4. permutedGroups(List> elementLists)
5. permuteList(List list, int[] permutations)
6. permuteList(List list, Integer[] permutation)
7. permVisit(int[] value, int n, int k, List res)