Java Number Min Value minimumEditDistance(String target, String source)

Description

Computes the minimum edit distance between two strings.

License

Open Source License

Parameter

Parameter	Description
target	the target string
source	the source string

Return

the minimum edit distance

Declaration

public static int minimumEditDistance(String target, String source) 

Method Source Code

//package com.java2s;
/*/*from ww w. j  av  a2 s. c  o  m*/
 * org.daisy.util (C) 2005-2008 Daisy Consortium
 * 
 * This library is free software; you can redistribute it and/or modify it under
 * the terms of the GNU Lesser General Public License as published by the Free
 * Software Foundation; either version 2.1 of the License, or (at your option)
 * any later version.
 * 
 * This library 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 Lesser General Public License for more
 * details.
 * 
 * You should have received a copy of the GNU Lesser General Public License
 * along with this library; if not, write to the Free Software Foundation, Inc.,
 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

public class Main {
    private static final int MED_INS_COST = 1;
    private static final int MED_SUBST_COST = 2;
    private static final int MED_DEL_COST = 1;

    /**
     * Computes the minimum edit distance between two strings.
     * @param target the target string
     * @param source the source string
     * @return the minimum edit distance
     */
    public static int minimumEditDistance(String target, String source) {
        int n = target.length();
        int m = source.length();
        int distance[][] = new int[n + 1][m + 1];
        for (int i = 0; i <= n; ++i) {
            distance[i][0] = i;
        }
        for (int j = 0; j <= m; ++j) {
            distance[0][j] = j;
        }
        for (int i = 1; i <= n; ++i) {
            char target_i = target.charAt(i - 1);
            for (int j = 1; j <= m; ++j) {
                char source_j = source.charAt(j - 1);
                int subst_cost = (target_i == source_j) ? 0 : MED_SUBST_COST;
                distance[i][j] = min(distance[i - 1][j] + MED_INS_COST, distance[i - 1][j - 1] + subst_cost,
                        distance[i][j - 1] + MED_DEL_COST);
            }
        }
        return distance[n][m];
    }

    /**
     * Find the lowest value between three integers. 
     * @return the lowest value
     */
    private static int min(int a, int b, int c) {
        int min = a;
        if (b < min) {
            min = b;
        }
        if (c < min) {
            min = c;
        }
        return min;
    }
}

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2. minimum(int a, int b, int c)
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8. minIndex(int ix1, int ix2)
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