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diff --git a/jni/feature_stab/db_vlvm/db_utilities_random.h b/jni/feature_stab/db_vlvm/db_utilities_random.h
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+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * 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.
+ */
+
+/* $Id: db_utilities_random.h,v 1.1 2010/08/19 18:09:20 bsouthall Exp $ */
+
+#ifndef DB_UTILITIES_RANDOM
+#define DB_UTILITIES_RANDOM
+
+#include "db_utilities.h"
+
+
+
+/*****************************************************************
+*    Lean and mean begins here                                   *
+*****************************************************************/
+/*!
+ * \defgroup LMRandom (LM) Random numbers, random sampling
+ */
+/*\{*/
+/*!
+ Random Number generator. Initialize with non-zero
+integer value r. A double between zero and one is
+returned.
+\param r    seed
+\return random double
+*/
+inline double db_QuickRandomDouble(int &r)
+{
+    int c;
+    c=r/127773;
+    r=16807*(r-c*127773)-2836*c;
+    if(r<0) r+=2147483647;
+    return((1.0/((double)2147483647))*r);
+    //return (((double)rand())/(double)RAND_MAX);
+}
+
+/*!
+Random Number generator. Initialize with non-zero
+integer value r. An int between and including 0 and max
+ \param r    seed
+ \param max    upped limit
+ \return random int
+*/
+inline int db_RandomInt(int &r,int max)
+{
+    double dtemp;
+    int itemp;
+    dtemp=db_QuickRandomDouble(r)*(max+1);
+    itemp=(int) dtemp;
+    if(itemp<=0) return(0);
+    if(itemp>=max) return(max);
+    return(itemp);
+}
+
+/*!
+ Generate a random sample indexing into [0..pool_size-1].
+ \param s            sample (out) pre-allocated array of size sample_size
+ \param sample_size    size of sample
+ \param pool_size    upper limit on item index
+ \param r_seed        random number generator seed
+ */
+inline void db_RandomSample(int *s,int sample_size,int pool_size,int &r_seed)
+{
+    int temp,temp2,i,j;
+
+    for(i=0;i<sample_size;i++)
+    {
+        temp=db_RandomInt(r_seed,pool_size-1-i);
+
+        for(j=0;j<i;j++)
+        {
+            if(s[j]<=temp) temp++;
+            else
+            {
+                /*swap*/
+                temp2=temp;
+                temp=s[j];
+                s[j]=temp2;
+            }
+        }
+        s[i]=temp;
+    }
+}
+/*\}*/
+#endif /* DB_UTILITIES_RANDOM */