guagua

版权声明：转载时请以超链接形式标明文章原始出处和作者信息及本声明
http://uestcguagua.blogbus.com/logs/12790785.html

 (由于时间有限，只做了找到所有频繁项集的部分)

由于复制过来的代码没有缩进和部分缺失等原因,我将这两个文件传到了空间里,有兴趣可以到这里下载:

http://www.adrive.com/public/1f63e8a59e27d1f1cd95c1e3f190c88b6e18a9db5b0effd7265fcd513820843e.html

ItemSet.cs

using System;
using System.Collections.Generic;
using System.Text;
using System.Collections;

namespace testApriori1
{
public class ItemSet
{
private string items;
private int sup;
public string Items
{
get { return items; }
set { items = value; }
}
public int Sup
{
get { return sup; }
set { sup = value; }
}
public ItemSet()//对象初始化
{
items = null;
sup = 0;
}
}
}

TestApriori.cs

using System;
using System.Collections.Generic;
using System.Text;
using System.Data;
using System.Data.SqlClient;
using System.Text.RegularExpressions;
using System.Collections;

namespace testApriori1
{
public class TestApriori
{
static void Main(string[] args)
{
Console.Write(DateTime.Now);
ArrayList D = GetEventsFromDB();//事务数据集
ArrayList I = GetItems1FromDB();//初始项目集合
float s = 0.01f;//支持度

List L = new List();//所有频繁项集
L = Apriori(D, I, s);

for (int i = 0; i < L.Count; i++)
{
Console.WriteLine(L[i].Items);
Console.WriteLine(L[i].Sup);
}
Console.Write(DateTime.Now);
Console.Read();
}

#region-----用Apriori算法进行迭代-----
///
/// 用Apriori算法进行迭代
///
///
///
///
///
static List Apriori(ArrayList D,ArrayList I,float sup)
{
List L = new List();//所有频繁项集
if (I.Count == 0) return L;
else
{
int[] Icount = new int[I.Count];//初始项集计数器,初始化为0
ArrayList Ifrequent = new ArrayList();//初始项集中的频繁项集

//遍历事务数据集，对项集进行计数
Regex r=new Regex(",");
for (int i = 0; i < D.Count; i++)
{
string[] subD=r.Split(D[i].ToString());
for (int j = 0; j < I.Count;j++ )
{
string[] subI = r.Split(I[j].ToString());
bool subIInsubD=true;
for(int m=0;m
{
bool subImInsubD=false;
for(int n=0;n
if (subI[m] == subD[n])
{
subImInsubD = true;
continue;
}
if(subImInsubD==false) subIInsubD=false;
}
if(subIInsubD==true) Icount[j]++;
}
}

//从初始项集中将支持度大于给定值的项转到L中
for (int i = 0; i < Icount.Length;i++ )
{
if (Icount[i] >= sup * D.Count)
{
Ifrequent.Add(I[i]);
ItemSet iSet = new ItemSet();
iSet.Items=I[i].ToString();
iSet.Sup = Icount[i];
L.Add(iSet);
}
}

I.Clear();
I = AprioriGen(Ifrequent);

L.AddRange(Apriori(D, I, sup));
return L;
}
}
#endregion-----用Apriori算法进行迭代-----

#region-------Apriori-gen生成候选项集---------
///
/// Apriori-gen生成候选项集
///
///
///
static ArrayList AprioriGen(ArrayList L)
{
ArrayList Lk=new ArrayList();
Regex r=new Regex(",");
for(int i=0;i
{
string[] subL1 = r.Split(L[i].ToString());
for(int j=i+1;j
{
string[] subL2 = r.Split(L[j].ToString());
//比较L中的两个项集将它们的并集暂存于temp中
string temp = L[j].ToString();//存储两个项集的并集
for(int m=0;m
{
bool subL1mInsubL2=false;
for(int n=0;n
{
if (subL1[m] == subL2[n]) subL1mInsubL2 = true;
}
if (subL1mInsubL2 == false) temp = temp + "," + subL1[m];
}
//当temp包含的项为（L中项集的大小）+1并且所求候选项集中没有与temp一样的项集
string[] subTemp = r.Split(temp);
if (subTemp.Length == subL1.Length + 1)
{
bool isExists = false;
for (int m = 0; m < Lk.Count; m++)
{
bool isContained = true;
for (int n = 0; n < subTemp.Length; n++)
{
if (!Lk[m].ToString().Contains(subTemp[n])) isContained=false;
}
if (isContained == true) isExists = true;
}
if(isExists==false) Lk.Add(temp);
}

}
}
return Lk;
}
#endregion-------Apriori-gen生成候选项集---------

#region-------从数据库中得到候选一项集---------
///
/// 从数据库中得到候选一项集
///
///
static ArrayList GetItems1FromDB()
{
string commandString = "select distinct Model from dbo.vAssocSeqLineItems";
DataSet ds = ExcuteDataSetByCommandString(commandString);

int countItems1 = 0;
countItems1 = ds.Tables[0].Rows.Count;

ArrayList Items1 = new ArrayList();
for (int i = 0; i < countItems1; i++)
Items1.Add(ds.Tables[0].Rows[i]["Model"].ToString());
return Items1;
}
#endregion-------从数据库中得到候选一项集---------

#region--------从数据库中获得事务集--------
///
/// 从数据库中获得事务集
///
///
static ArrayList GetEventsFromDB()
{
string commandString="select count(OrderNumber) from vAssocSeqOrders";
DataSet ds=ExcuteDataSetByCommandString(commandString);
int countEvent = Convert.ToInt32(ds.Tables[0].Rows[0][0]);//获得事务的数目


ArrayList events=new ArrayList();
string temp=null;

string orderNumber=null;//暂存数据表中的OrderNumber,用来判断是否是同一个Order
//获得所有的事务
commandString = "select OrderNumber,Model from vAssocSeqLineItems";
ds = ExcuteDataSetByCommandString(commandString);

for (int i = 0; i < ds.Tables[0].Rows.Count; i++)
{
if (orderNumber == null)//第一次读数据
{
orderNumber = ds.Tables[0].Rows[i]["OrderNumber"].ToString();
temp = ds.Tables[0].Rows[i]["Model"].ToString();
}
else if (orderNumber == ds.Tables[0].Rows[i]["OrderNumber"].ToString())//读同一个Order中的数据
{
temp = temp +","+ ds.Tables[0].Rows[i]["Model"];
}
else//读到另一个Order中的数据
{
events.Add(temp);
orderNumber = ds.Tables[0].Rows[i]["OrderNumber"].ToString();
temp=ds.Tables[0].Rows[i]["Model"].ToString();
}
if (i == ds.Tables[0].Rows.Count - 1) events.Add(temp);

}
return events;
}
#endregion--------从数据库中获得事务集--------

#region-----由指定的commandString从数据库中获得数据------
///
/// 由指定的commandString从数据库中获得数据
///
///
///
static DataSet ExcuteDataSetByCommandString(string commandString)
{
string connectionString = "server=.;database=AdventureWorksDW;trusted_connection=true";
SqlConnection sqlCon = new SqlConnection(connectionString);
sqlCon.Open();

SqlCommand sqlCmd = new SqlCommand();
sqlCmd.Connection = sqlCon;
sqlCmd.CommandText = commandString;

DataSet ds = new DataSet();
SqlDataAdapter sqlAdapter = new SqlDataAdapter(sqlCmd);
sqlAdapter.Fill(ds);

sqlCon.Close();
return ds;
}
#endregion-----由指定的commandString从数据库中获得数据------
}
}