2015年2月23日星期一

Rule of 72

How to remember rule of 72 rule?

1. Raise up right hand's middle finger

2. Flip all your 10 fingers up side down

3. The 7 and 2 are the numerator at the upper positor

4. Put the rate of return at the denominator

5. Division gives the number of year to get back the initial captial

2015年2月18日星期三

A program to read CSV file with time elapsed reported

File:

"0#AU113554908=",6261,88,214
"![WTCL9700I6",4128,132,758
"/JNKO201504900.U",4007,115,575
"/2EH9675D5",4911,244,22

Code:
#include <iostream>
#include <fstream>
#include <iterator>
#include <sstream>
#include <vector>
#include <string>
#include <ctime>

using namespace std;

class CSVRow
{
public:
string const& operator[](size_t index) const
{
return vTokens[index];
}
size_t size() const
{
return vTokens.size();
}
void readNextRow(istream& str)
{
string line;
getline(str, line);

stringstream lineStream(line);
string token;

vTokens.clear();
while(getline(lineStream, token, ','))
{
vTokens.push_back(token);
}
}
private:
vector<string> vTokens;
};

istream& operator>>(istream& str, CSVRow& data)
{
data.readNextRow(str);
return str;
}

class Timer
{
string s;
clock_t t;
public:
Timer(string s="") : t(clock()), s(s) {}
~Timer()
{
cout << "Function " + s + " elapsed in seconds [" << double(clock() - t) / CLOCKS_PER_SEC << "]" << '\n';
};
};

class Instrument
{
public:
string name;
int pe;
int recordType;
int exchangeID;
Instrument():name(""), pe(0), recordType(0), exchangeID(0) {}
Instrument (const string & name, int pe, int recordType, int exchangeID)
: name(name), pe(pe), recordType(recordType), exchangeID(exchangeID) {}
};

void TestRouteine(const string & filepath, vector<Instrument> & vInstruments)
{
volatile Timer timer("ReadCSV");
vInstruments.reserve(40000000);
ifstream fs(filepath);
CSVRow row;
while (fs >> row)
{
vInstruments.push_back(Instrument(row[0], atoi(row[1].c_str()), atoi(row[2].c_str()), atoi(row[3].c_str())));
}

cout << "size: [" << vInstruments.size() << "]" << endl;
}

int main()
{
vector<Instrument> vInstruments(40000000);
TestRouteine("../InstradayWS/pen201502131002.txt", vInstruments);
system("PAUSE");
}

2015年2月6日星期五

Regular Expression to match the error code of IIS FTP Log

Regular Expression to match the error code of IIS FTP Log

.*21\s(.*?)\s(.*?)\s[45]

2015-02-01 00:00:14 194.20.113.170 UK2I-ISASAAC01\isat.internal 194.20.113.192 21 NOOP - 200 0 0 f51b3e27-ca5c-4ff4-8f6e-b7b4e12fa6d4 -
2015-02-01 00:00:14 194.20.113.170 UK2I-ISASAAC01\isat.internal 194.20.113.192 21 CWD /NDA 250 0 0 f51b3e27-ca5c-4ff4-8f6e-b7b4e12fa6d4 /NDA
2015-02-01 00:00:14 194.20.113.170 UK2I-ISASAAC01\isat.internal 194.20.113.192 21 PWD - 257 0 0 f51b3e27-ca5c-4ff4-8f6e-b7b4e12fa6d4 -
2015-02-01 00:00:14 194.20.113.170 UK2I-ISASAAC01\isat.internal 194.20.113.192 21 NOOP - 200 0 0 f51b3e27-ca5c-4ff4-8f6e-b7b4e12fa6d4 -
2015-02-01 00:00:14 194.20.113.170 UK2I-ISASAAC01\isat.internal 194.20.113.192 21 CWD /NDA_Staging 250 0 0 f51b3e27-ca5c-4ff4-8f6e-b7b4e12fa6d4 /NDA_Staging

using Windows findstr
findstr /N /R /C:".*21[ ].*[ ].*[ ][45][0-9][0-9][ ]" *.log > ftpec.txt

findstr /N /R /C:".*[ ][45][0-9][0-9][ ]" *.log > ftpec.txt

2015年2月4日星期三

Regular Expression

http://stackoverflow.com/questions/406230/regular-expression-to-match-string-not-containing-a-word

I know it is possible to match for the word and using tools options reverse the match. (eg. by grep -v) However I want to know if it is possible using regular expressions to match lines which does not contain a specific word, say hede?

Input:

Hoho
Hihi
Haha
hede

# grep "Regex for do not contain hede" Input

Output:

Hoho
Hihi
Haha


Note that the solution to does not start with “hede”:
^(?!hede).*$

is generally much more efficient than the solution to does not contain “hede”:
^((?!hede).)*$

The former checks for “hede” only at the input string’s first position, rather than at every position.

How to remove new line in Notepad++?


You need something like a regular expression.

You have to be in Extended mode

If you want all the lines to end up on a single line use \r\n. If you want to simply remove emptylines, use \n\r as @Link originally suggested.

Replace either expression with nothing.

2015年2月2日星期一

XPath语法在C#中使用XPath示例

http://www.cnblogs.com/yukaizhao/archive/2011/07/25/xpath.html

XPath语法在C#中使用XPath示例

XPath可以快速定位到Xml中的节点或者属性。XPath语法很简单，但是强大够用，它也是使用xslt的基础知识。

示例Xml：

<?xml version="1.0" encoding="utf-8" ?>

<pets>

  <cat color="black" weight="10">

    <price>100</price>

    <desc>this is a black cat</desc>

  </cat>

  <cat color="white" weight="9">

    <price>80</price>

    <desc>this is a white cat</desc>

  </cat>

  <cat color="yellow" weight="15">

    <price>80</price>

    <desc>this is a yellow cat</desc>

  </cat>

  <dog color="black" weight="10">

    <price>100</price>

    <desc>this is a black dog</desc>

  </dog>

  <dog color="white" weight="9">

    <price>80</price>

    <desc>this is a white dog</desc>

  </dog>

  <dog color="yellow" weight="15">

    <price>80</price>

    <desc>this is a yellow dog</desc>

  </dog>

</pets>

XPath的语法：

1. XPath中的符号

符号	说明	示例	示例说明
/	表示从根节点开始选择	/pets	选择根节点pets
/	表示节点和子节点之间的间隔符	/pets/dog	选择pets节点下的dog节点
//xx	表示从整个xml文档中查找，而不考虑当前节点位置	//price	选择文档中所有的price节点
.	单个英文半角句点表示选择当前节点	/pets/.	选择pets节点
..	双点，表示选择父节点	/pets/dog[0]/..	表示pets节点，也就是第一个dog节点的父节点
@xx	表示选择属性	//dog/@color	表示选择所有dog节点的color属性集合
[…]	中括号表示选择条件，括号内为条件	//dog[@color=’white’]	所有color为white的dog节点
	中括号表示选择条件，括号内为条件	//dog[/price<100]	所有price字节点值小于100的dog节点
	中括号内数字为节点索引，类似c#等语言中的数组,数组下标是从1开始的	//dog[1]	第1个dog节点
	中括号内数字为节点索引，类似c#等语言中的数组,数组下标是从1开始的	//dog[last()]	最后一个dog节点，last()是xPath内置函数
\|	单竖杠表示合并节点结合	//dog[@color=’white’] \| //cat[@color=’white’]	color属性为white的dog节点和color属性为white的cat节点
*	星号表示任何名字的节点或者属性	//dog/*	表示dog节点的所有子节点
*	星号表示任何名字的节点或者属性	//dog/@*	表示dog节点的所有属性节点

2. XPath数学运算符

+ 加号表示加

- 表示数字相减

* 表示乘以

div 表示除以，这里数学上的除号/已经被用作节点之间分隔符了

mod 表示取余

3. XPath逻辑运算符

= 等于，相当于c#中的 ==

!= 不等于

> 大于

>= 大于等于

< 小于

<= 小于等于

and 并且与关系

or 或者或关系

4. XPath Axes 从字面翻译这个是XPath轴的意思，但根据我的理解这个翻译成XPath节点关系运算关键字更合适，就是一组关键字加上::双冒号表示和当前节点有关系的一个或者一组节点.

使用语法： axisname::nodetest[predicate] 即轴名字::节点名字[取节点条件]

具体说明如下：

关键字	说明	示例	示例说明
ancestor	当前节点的父祖节点	ancestor::pig	当前节点的祖先节点中的pig节点
ancestor-or-self	当前节点以及其父祖节点	ancestor::pig
attribute	当前节点的所有属性	attribute::weight	相当于@weight，attribute::和@是等价的
child	当前节点的所有字节点	child::*[name()!=’price’]	选择名字不是price的子节点
descendant	子孙节点	descendant::[@]	有属性的子孙节点
descendant-or-self	子孙节点以及当前节点	descendant-or-self::*
following	Xml文档中当前节点之后的所有节点	following::*
following-sibling	当前节点的同父弟弟节点	following-sibling::
preceding	Xml文档中当前节点之前的所有节点	preceding::*
namespace	选取当前节点的所有命名空间节点	namespace::*
parent	当前节点的父节点	parent::	相当于双点..
preceding-sibling	当前节点之后的同父兄节点	preceding-sibling::*
self	当前节点	self::*	相当于单点.

5. 常用的XPath函数介绍：

在XPath表达式中常用的函数有下面两个：

position() 表示节点的序号例如 //cat[position() = 2] 表示取序号为2的dog节点

last() 表示取最后一个节点 //cat[last()]

name() 表示当前节点名字 /pets/*[name() != 'pig'] 表示/pets下名字不是pig的子节点

XPath的函数还有很多，包括字符串函数，数字函数和时间函数等，具体可以参考w3的网站。

以上是XPath的语法，下面我们看下如何在.Net中使用XPath

在.Net中可以通过XPathDocument或者XmlDocument类使用XPath。XPathDocument是只读的方式定位Xml节点或者属性文本等，而XmlDocument则是可读写的。

如下代码示例展示了如何使用XPathDocument和XmlDocument。

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Xml.XPath;

using System.Xml;

namespace UseXPathDotNet

{

    class Program

    {

        static void Main(string[] args)

        {

            UseXPathWithXPathDocument();

            UseXPathWithXmlDocument();

            Console.Read();

        }

        static void UseXPathWithXmlDocument()

        {

            XmlDocument doc = new XmlDocument();

            doc.Load("http://www.cnblogs.com/yukaizhao/rss");

            //使用xPath选择需要的节点

            XmlNodeList nodes = doc.SelectNodes("/rss/channel/item[position()<=10]");

            foreach (XmlNode item in nodes)

            {

                string title = item.SelectSingleNode("title").InnerText;

                string url = item.SelectSingleNode("link").InnerText;

                Console.WriteLine("{0} = {1}", title, url);

            }

        }

        static void UseXPathWithXPathDocument()

        {

            XPathDocument doc = new XPathDocument("http://www.cnblogs.com/yukaizhao/rss");

            XPathNavigator xPathNav = doc.CreateNavigator();

            //使用xPath取rss中最新的10条随笔

            XPathNodeIterator nodeIterator = xPathNav.Select("/rss/channel/item[position()<=10]");

            while (nodeIterator.MoveNext())

            {

                XPathNavigator itemNav = nodeIterator.Current;

                string title = itemNav.SelectSingleNode("title").Value;

                string url = itemNav.SelectSingleNode("link").Value;

                Console.WriteLine("{0} = {1}",title,url);

            }

        }

    }

}

XPath使用示例，请看下面的代码注释　

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.IO;

using System.Xml;

namespace UseXPath1

{

    class Program

    {

        static void Main(string[] args)

        {

            string xml = @"<?xml version=""1.0"" encoding=""utf-8"" ?>

<pets>

  <cat color=""black"" weight=""10"" count=""4"">

    <price>100</price>

    <desc>this is a black cat</desc>

  </cat>

  <cat color=""white"" weight=""9"" count=""5"">

    <price>80</price>

    <desc>this is a white cat</desc>

  </cat>

  <cat color=""yellow"" weight=""15"" count=""1"">

    <price>110</price>

    <desc>this is a yellow cat</desc>

  </cat>

  <dog color=""black"" weight=""10"" count=""7"">

    <price>114</price>

    <desc>this is a black dog</desc>

  </dog>

  <dog color=""white"" weight=""9"" count=""4"">

    <price>80</price>

    <desc>this is a white dog</desc>

  </dog>

  <dog color=""yellow"" weight=""15"" count=""15"">

    <price>80</price>

    <desc>this is a yellow dog</desc>

  </dog>

    <pig color=""white"" weight=""100"" count=""2"">

    <price>8000</price>

    <desc>this is a white pig</desc>   

    </pig>

</pets>";

            using (StringReader rdr = new StringReader(xml))

            {

                XmlDocument doc = new XmlDocument();

                doc.Load(rdr);

                //取所有pets节点下的dog字节点

                XmlNodeList nodeListAllDog = doc.SelectNodes("/pets/dog");

                //所有的price节点

                XmlNodeList allPriceNodes = doc.SelectNodes("//price");

                //取最后一个price节点

                XmlNode lastPriceNode = doc.SelectSingleNode("//price[last()]");

                //用双点号取price节点的父节点

                XmlNode lastPriceParentNode = lastPriceNode.SelectSingleNode("..");

                //选择weight*count=40的所有动物，使用通配符*

                XmlNodeList nodeList = doc.SelectNodes("/pets/*[@weight*@count=40]");

                //选择除了pig之外的所有动物,使用name()函数返回节点名字

                XmlNodeList animalsExceptPigNodes = doc.SelectNodes("/pets/*[name() != 'pig']");

                //选择价格大于100而不是pig的动物

                XmlNodeList priceGreaterThan100s = doc.SelectNodes("/pets/*[price div @weight >10 and name() != 'pig']");

                foreach (XmlNode item in priceGreaterThan100s)

                {

                    Console.WriteLine(item.OuterXml);

                }

                //选择第二个dog节点

                XmlNode theSecondDogNode = doc.SelectSingleNode("//dog[position() = 2]");

                //使用xpath ，axes 的 parent 取父节点

                XmlNode parentNode = theSecondDogNode.SelectSingleNode("parent::*");

                //使用xPath选择第二个dog节点前面的所有dog节点

                XmlNodeList dogPresibling = theSecondDogNode.SelectNodes("preceding::dog");

                //取文档的所有子孙节点price

                XmlNodeList childrenNodes = doc.SelectNodes("descendant::price");

            }

            Console.Read();

        }

    }

}