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What does $_ mean in PowerShell?
...he current value in the pipe line, which is called $PSItem in Powershell 3 and newer.
1,2,3 | %{ write-host $_ }
or
1,2,3 | %{ write-host $PSItem }
For example in the above code the %{} block is called for every value in the array. The $_ or $PSItem variable will contain the current value...
Capturing TAB key in text box [closed]
...call the preventDefault() method on the event object passed to your event handler. In IE, you have to return false from the event handle. The JQuery library provides a preventDefault method on its event object that works in IE and FF.
<body>
<input type="text" id="myInput">
<script t...
Controlling number of decimal digits in print output in R
...te a print function that ignored the options value. The built-in printing and formatting functions do use the options value as a default.
As to the second question, since R uses finite precision arithmetic, your answers aren't accurate beyond 15 or 16 decimal places, so in general, more aren't req...
常用Linux命令详解（持续更新） - 更多技术 - 清泛网 - 专注C/C++及内核技术
...常工作中经常会用到的一些Linux命令进行一下详解。logout,shutdown,reboot,useradd,passwd,ls,ll,cd,mkdir,vi,cp,rm,mv,chmod,chown,find,grep,tail,tar,gzip,fdisk,kill,netstat等。一、注销，关机，重启，新建用户、删除用户
1. 注销系统的命令
logout 、exit
这...
Is there any way to git checkout previous branch?
... sort of want the equivalent of cd - for git. If I am in branch master and I checkout foo , I would love to be able to type something like git checkout - to go back to master , and be able to type it again to return to foo .
...
How to merge lists into a list of tuples?
...d I create [(1,5), (1,6), (1,7), (1,8), (2,5), (2,6) ,so on] using zip command?
– Mona Jalal
May 30 '16 at 4:39
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getting the screen density programmatically in android?
How to get the screen density programmatically in android?
19 Answers
19
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Using ViewPagerIndicator library with Android Studio and Gradle
...cator library , but I'm unable to get it working with my Gradle project in Android Studio.
19 Answers
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What is the difference between a URI, a URL and a URN?
People talk about URL s, URI s, and URN s as if they're different things, but they look the same to the naked eye.
31 An...
Shortcut for creating single item list in C#
...is does seems sort of strange, but I like the utility of it. Thanks Martin and Jon.
– Ryan Ische
Jan 20 '09 at 20:08
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