1.代码

import java.io.Serializable;import java.util.NavigableMap;import java.util.Random;import java.util.TreeMap;public class Zifp_gen implements Serializable {    private Random random = new Random(0);    NavigableMap
     
       map;    private static final double Constant = 1.0;       public  Zifp_gen(int nums, double skewness) {        // create the TreeMap        map = computeMap(nums, skewness);    }    //size为rank个数，skew为数据倾斜程度, 取值为0表示数据无倾斜，取值越大倾斜程度越高    private static NavigableMap
      
        computeMap(            int size, double skew) {        NavigableMap
       
         map =                new TreeMap
        
         ();        //总频率        double div = 0;        //对每个rank，计算对应的词频，计算总词频        for (int i = 1; i <= size; i++) {            //the frequency in position i            div += (Constant / Math.pow(i, skew));        }        //计算每个rank对应的y值，所以靠前rank的y值区间远比后面rank的y值区间大        double sum = 0;        for (int i = 1; i <= size; i++) {            double p = (Constant / Math.pow(i, skew)) / div;            sum += p;            map.put(sum, i - 1);        }        return map;    }//    public int next() {         // [1,n]//        double value = random.nextDouble();//        //找最近y值对应的rank//        return map.ceilingEntry(value).getValue() + 1;//    }}
        
       
      
     

2.test

import java.util.NavigableMap; public class Test {    public static void main(String args[]){        Zifp_gen z1=new Zifp_gen(100,1.0);        for (NavigableMap.Entry
     
       entry : z1.map.entrySet()) {            System.out.println("Key = " + entry.getKey() + ", Value = " + entry.getValue());        }    }  }
     

 原Zipf齐夫分布及Java实现

 

zipf数据写入外部文本

public class Test {    public static void main(String args[]) throws IOException{        Zifp_gen z1=new Zifp_gen(100,0.5);        PrintWriter pw=new PrintWriter(new FileWriter("F:\\zipf_100_0.5.txt"));        for (NavigableMap.Entry
     
       entry : z1.map.entrySet()) {           // System.out.println("Key = " + entry.getKey() + ", Value = " + entry.getValue());           // String str="Key = " + entry.getKey() + ", Value = " + entry.getValue();            String str= entry.getKey() + " " ;            pw.println(str);        }        pw.close();    }    }