private void CreateNode_Multistate(XmlNode theXmlNode)
{
XmlAttributeCollection attr = theXmlNode.Attributes;
int range = Convert.ToInt32(attr.GetNamedItem("Range").Value);
// 新建节点并添加值
int nid = m_bnNodes.Count;
BNode newBNode = new BNode(theXmlNode.Name.ToLower(), nid, range);
//标注出所有节点的父节点以及子节点
XmlNodeList xmlNodes = theXmlNode.SelectNodes("Parents/*");
foreach (XmlNode xml_node in xmlNodes)
{
foreach (BNode bn_node in m_bnNodes)
{
if (xml_node.Name.ToLower() == bn_node.Name)
{
bn_node.children.Add(newBNode);
newBNode.Parents.Add(bn_node);
break;
}
}
}
// 对每个节点新建一个条件概率表
int table_rows = 1;
xmlNodes = theXmlNode.SelectNodes("CPT_Col");
//if (range != xmlNodes.Count + 1) throw new Exception("CPT cols mismatch");
int cond_rows = 1;
if (newBNode.Parents.Count != 0)
{
foreach (BNode bn_node in newBNode.Parents)
{
table_rows *= bn_node.Range;
cond_rows *= bn_node.Range;
}
}
table_rows *= newBNode.Range;
newBNode.CPT = new double[cond_rows, range];
//为条件概率表添加通过学习已得到的参数
for (int i = 0; i < xmlNodes.Count; ++i)
{
XmlNodeList cpNodes = xmlNodes[i].SelectNodes("CP");
if (cpNodes.Count != table_rows)
{
throw new Exception("CPT Rows mismatch");
}
//所有情况按字典序进行排序
int now = 0;
for (int j = 0; j < cond_rows; ++j)
{
double pr = 0;
for (int k = 0; k < range; ++k)
{
newBNode.CPT[j, k] = Convert.ToDouble(cpNodes[now].InnerText);
now += 1;
pr += newBNode.CPT[j, k];
}
if (pr > 1.0 && pr < 1.0)
{
throw new Exception("Probability does not normalize");
}
}
}
m_bnNodes.Add(newBNode);
}
protected double Sampling(int prob, int probcon)
{
mq = 0;
int T = 10000; //采样个数
First_Sampling(); //第一次随机抽样
Random random = new Random(GetRandomSeedbyGuid());
int sample = random.Next();
if (the_sample[prob] == probcon)
{
mq = mq + 1;
}
double pr = 0.0;
double this_pr, multipr1, multipr2;
nxt_sample = the_sample;
for (int i = 2; i < T; i++)
{
this_pr = 1;
multipr1 = 1;
multipr2 = 1;
the_sample = nxt_sample;
//确定抽样时所需要的近似概率
for (int j = 0; j < m_net.Nodes.Count; j++)
{
BNode theNode = (BNode)m_net.Nodes[j];
int cond = 0;
multipr1 = 1;
multipr2 = 1;
int flag = 0;
if (theNode.Evidence == -1)
{
if (theNode.Parents.Count != 0)
{
foreach (BNode node in theNode.Parents)
{
cond = cond * 2 + the_sample[node.ID];
}
multipr1 = multipr1 * theNode.CPT[cond, 0];
multipr2 = multipr2 * theNode.CPT[cond, 1];
}
else
{
multipr1 = multipr1 * theNode.CPT[0, 0];
multipr2 = multipr2 * theNode.CPT[0, 1];
}
foreach (string item in strs)
{
if (theNode.Name.Contains(item))
{
this_pr = theNode.CPT[cond, 0];
random = new Random(GetRandomSeedbyGuid());
sample = random.Next();
if (sample % 10000000 > this_pr * 10000000)
{
nxt_sample[j] = 1;
}
else
{
nxt_sample[j] = 0;
}
flag = 1;
}
}
if (flag == 1)
{
continue;
}
if (theNode.children.Count != 0)
{
int cond1 = 0;
int cond2 = 0;
foreach (BNode node in theNode.children)
{
cond1 = 0;
cond2 = 0;
foreach (BNode parent in node.Parents)
{
if (parent.ID != theNode.ID)
{
cond1 = cond1 * parent.Range + the_sample[parent.ID];
cond2 = cond2 * parent.Range + the_sample[parent.ID];
}
else
{
cond1 = cond1 * theNode.Range + 0;
cond2 = cond2 * theNode.Range + 1;
}
}
multipr1 = multipr1 * node.CPT[cond1, the_sample[node.ID]];
multipr2 = multipr2 * node.CPT[cond2, the_sample[node.ID]];
}
}
this_pr = multipr1 / (multipr1 + multipr2);
random = new Random(GetRandomSeedbyGuid());
sample = random.Next();
if (sample % 10000000 > this_pr * 10000000)
{
nxt_sample[j] = 1;
}
else
{
nxt_sample[j] = 0;
}
}
}
if (nxt_sample[prob] == probcon)
{
mq = mq + 1;
}
}
pr = (double)mq / T;
return(pr);
}
private void CreateNode(XmlNode theXmlNode) //对每个节点的数据进行储存操作
{
//Attributes是对于每个节点的属性和值进行获取的函数
XmlAttributeCollection attr = theXmlNode.Attributes;
int range = Convert.ToInt32(attr.GetNamedItem("Range").Value);
// 新建节点并添加值
int nid = m_bnNodes.Count;
BNode newBNode = new BNode(theXmlNode.Name.ToLower(), nid, range);
//标注出所有节点的父节点以及子节点
XmlNodeList xmlNodes = theXmlNode.SelectNodes("Parents/*");
foreach (XmlNode xml_node in xmlNodes)
{
foreach (BNode bn_node in m_bnNodes)
{
if (xml_node.Name.ToLower() == bn_node.Name)
{
bn_node.children.Add(newBNode);
newBNode.Parents.Add(bn_node);
break;
}
}
}
// 对每个节点新建一个条件概率表
int table_rows = 1;
xmlNodes = theXmlNode.SelectNodes("CPT_Col");
if (range != xmlNodes.Count + 1)
{
throw new Exception("CPT cols mismatch");
}
foreach (BNode bn_node in newBNode.Parents)
{
table_rows *= bn_node.Range;
}
newBNode.CPT = new double[table_rows, range];
//为条件概率表添加通过学习已得到的参数
for (int i = 0; i < xmlNodes.Count; ++i)
{
XmlNodeList cpNodes = xmlNodes[i].SelectNodes("CP");
if (cpNodes.Count != table_rows)
{
throw new Exception("CPT Rows mismatch");
}
for (int j = 0; j < table_rows; ++j)
{
newBNode.CPT[j, i] = Convert.ToDouble(cpNodes[j].InnerText);
}
}
for (int i = 0; i < table_rows; ++i)
{
double pr = 1.0;
for (int j = 0; j < range - 1; ++j)
{
pr -= newBNode.CPT[i, j];
}
if (pr < 0)
{
throw new Exception("Probability does not normalize");
}
newBNode.CPT[i, range - 1] = pr;
}
m_bnNodes.Add(newBNode);
}
protected double Sum_Multistate(int nid, int para)
{
BNode theNode = (BNode)m_net.Nodes[nid];
Bucket theBuck = (Bucket)m_buckets[nid];
int p_cnt = 1;
foreach (BNode node in theNode.Parents)
{
p_cnt *= node.Range;
}
int cond = 0;
if (p_cnt != 1)
{
cond = para % p_cnt; //防止溢出
}
else
{
cond = 0;
}
double pr = 0.0;
for (int e = 0; e < theNode.Range; ++e)
{
if (theNode.Evidence != -1 && theNode.Evidence != e)
{
continue;
}
double tmpPr = theNode.CPT[cond, e];
foreach (Bucket nxtBuck in theBuck.childBuckets)
{
int next_para = 0;
int cond_new = 1;
int cond_pos = 1;
for (int j = 0; j < nxtBuck.parentNodes.Count; ++j)
{
BNode pnode = (BNode)nxtBuck.parentNodes[j];
int pos = theBuck.parentNodes.IndexOf(pnode);
int k;
cond_new = 1;
for (k = 0; k < j; ++k)
{
BNode panode = (BNode)nxtBuck.parentNodes[k];
cond_new *= panode.Range;
}
if (pos >= 0)
{
cond_pos = 1;
for (k = 0; k < pos; ++k)
{
BNode panode = (BNode)theBuck.parentNodes[k];
cond_pos *= panode.Range;
}
next_para += para / cond_pos * cond_new;
}
else
{
next_para += e * cond_new;
}
}
tmpPr *= Sum_Multistate(nxtBuck.id, next_para);
}
pr += tmpPr;
}
return(pr);
}