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How can I check for “undefined” in JavaScript? [duplicate]
...d undefined the code will throw an error, and it's easy to test - jsfiddle.net/WcM5g The proper way is typeof myVar === 'undefined'.
– laurent
Jul 11 '13 at 13:31
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Is there a better way to express nested namespaces in C++ within the header
...e is library.
I'd assume Microsoft is imitating here the success of the .NET Library, where namespaces contribute to the discoverability of the extensive library. (.NET has about 18000 types.)
I'd further assume that there is an optimal (order of magnitude of) symbols in a namespace. say, 1 doesn...
slashes in url variables
...r this.
Eg URLEncoder.encode(url, "UTF-8")
Then you can say
yourUrl = "www.musicExplained/index.cfm/artist/" + URLEncoder.encode(VariableName, "UTF-8")
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Installing older version of R package
...e on Windows, an equivalent using PowerShell would be:
(new-object System.Net.WebClient).DownloadFile("http://cran.r-project.org/src/contrib/Archive/ggplot2/ggplot2_0.9.1.tar.gz", "./ggplot2_0.9.1.tar.gz")
or you can just download the source from the CRAN archive via your web browser.
To instal...
Direct casting vs 'as' operator?
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The as keyword is good in asp.net when you use the FindControl method.
Hyperlink link = this.FindControl("linkid") as Hyperlink;
if (link != null)
{
...
}
This means you can operate on the typed variable rather then having to then cast it from obj...
CSS Pseudo-classes with inline styles
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Rather than needing inline you could use Internal CSS
<a href="http://www.google.com" style="hover:text-decoration:none;">Google</a>
You could have:
<a href="http://www.google.com" id="gLink">Google</a>
<style>
#gLink:hover {
text-decoration: none;
}
</...
Normalize data in pandas
...frame has strings in some columns, see this answer
– netskink
Jul 22 '18 at 0:21
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The name 'model' does not exist in current context in MVC3
...E,PATCH,OPTIONS" modules="IsapiModule" scriptProcessor="%windir%\Microsoft.NET\Framework\v4.0.30319\aspnet_isapi.dll" preCondition="classicMode,runtimeVersionv4.0,bitness32" responseBufferLimit="0" />
<add name="ExtensionlessUrlHandler-ISAPI-4.0_64bit" path="*." verb="GET,HEAD,POST,DEBUG...
PDO MySQL: Use PDO::ATTR_EMULATE_PREPARES or not?
...of the mysql client libraries, PDO will emulate them for you.
http://php.net/manual/en/ref.pdo-mysql.php
I ditched MySQLi for PDO for the prepared named statements and the better API.
However, to be balanced, PDO performs negligibly slower than MySQLi, but it's something to bear in mind. I knew ...
What is a C++ delegate?
... and wherever you like.
There are some very good examples here:
http://www.codeproject.com/Articles/7150/Member-Function-Pointers-and-the-Fastest-Possible
http://www.codeproject.com/Articles/11015/The-Impossibly-Fast-C-Delegates
http://www.codeproject.com/Articles/13287/Fast-C-Delegate
...