Java List Random Item resampleWithReplacement(final List l, final int n)

Description

resample With Replacement

License

Open Source License

Declaration

public static List resampleWithReplacement(final List l, final int n) 

Method Source Code

//package com.java2s;
/**// www  .j a v a 2s  .  c  o  m
 * Musite
 * Copyright (C) 2010 Digital Biology Laboratory, University Of Missouri
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

import java.util.ArrayList;

import java.util.List;
import java.util.Random;
import java.util.Set;

public class Main {
    /**
     *
     * @param N
     * @param n
     */
    public static List<Integer> resampleWithReplacement(final int N, final int n) {
        return resampleWithReplacement(N, n, new Random());
    }

    public static List<Integer> resampleWithReplacement(final int N, final int n, final Random rand) {
        return resampleWithReplacement(N, n, null, true, rand);
    }

    public static List<Integer> resampleWithReplacement(final int N, final int n,
            final Set<Integer> exclusiveIndicesFilter) {
        return resampleWithReplacement(N, n, exclusiveIndicesFilter, true);
    }

    public static List<Integer> resampleWithReplacement(final int N, final int n, final Set<Integer> indicesFilter,
            final boolean exclude) {
        return resampleWithReplacement(N, n, indicesFilter, exclude, new Random());
    }

    public static List<Integer> resampleWithReplacement(final int N, final int n, Set<Integer> indicesFilter,
            boolean exclude, final Random rand) {
        if (rand == null) {
            throw new NullPointerException();
        }

        if (N <= 0 || n <= 0) {
            throw new IllegalArgumentException();
        }

        List<Integer> indices = new ArrayList<Integer>(n);
        for (int i = 0; i < n;) {
            int ix = rand.nextInt(N);
            if (indicesFilter != null && indicesFilter.contains(ix) == exclude)
                continue;
            indices.add(ix);
            i++;
        }
        return indices;
    }

    public static List resampleWithReplacement(final List l, final int n) {
        return resampleWithReplacement(l, n, new Random());
    }

    public static List resampleWithReplacement(final List l, final int n, final Random rand) {
        return resampleWithReplacement(l, n, null, true, rand);
    }

    public static List resampleWithReplacement(final List l, final int n, Set<Integer> exclusiveIndicesFilter) {
        return resampleWithReplacement(l, n, exclusiveIndicesFilter, true);
    }

    public static List resampleWithReplacement(final List l, final int n, Set<Integer> indicesFilter,
            boolean exclude) {
        return resampleWithReplacement(l, n, indicesFilter, exclude, new Random());
    }

    public static List resampleWithReplacement(final List l, final int n, Set<Integer> indicesFilter,
            boolean exclude, final Random rand) {
        if (l == null || rand == null) {
            throw new NullPointerException();
        }

        int N = l.size();
        if (N <= 0 || n <= 0) {
            throw new IllegalArgumentException();
        }

        List ret = new ArrayList(n);
        for (int i = 0; i < n;) {
            int ix = rand.nextInt(N);
            if (indicesFilter != null && indicesFilter.contains(ix) == exclude)
                continue;
            ret.add(l.get(ix));
            i++;
        }

        return ret;
    }
}

Related

1. pickOneAtRandom(List list)
2. PickRandom(final Collection list)
3. pickRandom(LinkedList list, int n)
4. pickRandom(List collection)
5. pickupFromList(String[] list)
6. sample(List l, Random r)
7. sample(Random random, List list)
8. sampleRandomSublist(List list, int sampleSize)
9. sampleWithoutReplacement(List items, int sampleSize)